List of acronyms: S

This list contains acronyms, initialisms, and pseudo-blends that begin with the letter S.

For the purposes of this list:

• acronym = an abbreviation pronounced as if it were a word, e.g., SARS = severe acute respiratory syndrome, pronounced to rhyme with cars
• initialism = an abbreviation pronounced wholly or partly using the names of its constituent letters, e.g., CD = compact disc, pronounced cee dee
• pseudo-blend = an abbreviation whose extra or omitted letters mean that it cannot stand as a true acronym, initialism, or portmanteau (a word formed by combining two or more words).

(a) = acronym, e.g.: SARS – (a) Severe acute respiratory syndrome

(i) = initialism, e.g.: CD – (i) Compact disc

(p) = pseudo-blend, e.g.: UNIFEM – (p) United Nations Development Fund for Women

(s) = symbol (none of the above, representing and pronounced as something else; for example: MHz – Megahertz)

(Main list of acronyms)

• S
  • (s) Siemens
  • South
  • Sulphur/Sulfur

S0–9

• S4C — (i) Sianel Pedwar Cymru (Welsh, "Channel Four Wales")

SA

• sa — (s) Sanskrit language (ISO 639-1 code)
• SA
  • (s) Sand (METAR Code)
  • Saudi Arabia (ISO 3166 and FIPS 10-4 country code digram)
  • (i) Sexaholics Anonymous
  • (i) sine anno (Latin, “without year”)
  • Situational awareness
  • South Africa
  • (i/s) South Australia (postal symbol)
  • (i) Standards Australia
  • Sturmabteilung (German, “Storm Detachment”, Nazi forerunner and rival of SS)
• S.A. – designation for a corporation in many European countries; see article for meanings
• SAA
  • (i) Saudi Arabian Airlines, former name of Saudia
  • Sex Addicts Anonymous
  • South African Airways
  • Southern Athletic Association
  • Standards Association of Australia, a former name of Standards Australia
• SAAB — (a) Svenska Aeroplan AB (Swedish aircraft manufacturer; also refers to its former auto manufacturing arm)
• SAAFR — (a/i) Standard use Army Aircraft Flight Route (“safer”)
• SAAMI — (a) Sporting Arms and Ammunition Manufacturers' Institute (“sammy”)
• SAARC — (i) South Asian Association for Regional Cooperation
• SAB — (i) Soprano Alto Baritone
• Sabena — (a) Société anonyme belge d'exploitation de la navigation aérienne (French for “Belgian Company for Exploiting Aerial Navigation”, 1923–2001)
• SABIC — (p) Saudi Basic Industries Corporation
• SABR — (a) Society for American Baseball Research
• SAC
  • (a) Standards Activity Committee (of SISO)
  • U.S. Strategic Air Command (1946–1992)
• SACAT — (a) Semi Attended Customer Activated Terminal (Supermarket checkout)
• SACEUR — (p) Supreme Allied Commander EURope
• SACLANT — (p) Supreme Allied Commander atLANTic
• SACLOS — (a) Semi-Automatic Command to Line of Sight
• SAD
  • (s) Safford Regional Airport (IATA code)
  • (a) Seasonal Affective Disorder
  • Situational Awareness Display
• SADD — (a) originally Students Against Drunk Driving, now Students Against Destructive Decisions (U.S. national school-related group)
• SADL
  • (a) Situation Awareness Data Link (“saddle”)
  • Structural Architecture Description Language
• SAE
  • (i) Society of Automotive Engineers
  • Stamped addressed envelope
• SAFER — (a) Steel And Foam Energy Reduction
• SAFICT — (a) Software Agents as Facilitators of Interoperability in Collective Training
• sag — (s) Sango language (ISO 639-2 code)
• SAG — (i) Screen Actors Guild
• SAGAT — (a) Situation Awareness Global Assessment Technique
• SAGE — (a) Semi-Automatic Ground Environment (simulation)
• SAHB — (a) Sensational Alex Harvey Band
• SAIC — (i) Science Applications International Corporation
• SALT
  • (a/i) Save A Life Today (SALT) Alert; Emergency Contact System
  • (a) Southern African Large Telescope
  • Strategic Arms Limitation Talks
• SAM
  • (a) Sequential-Access Memory
  • Sociedad Aeronáutica de Medellín
  • Surface-to-Air Missile
• Sambo – (p/a) Samooborona bez oruzhiya (Russian: "Самооборона без оружия", literally "self-defense without weapons")
• SAML — (a) Security Assertion Markup Language (“sam-ell”)
• SANZAR — (a) South Africa, New Zealand, and Australia Rugby
• san
  • (s) Sanskrit language (ISO 639-2 code)
  • (a) Storage Area Network
• SAR
  • (s) Saudi riyal (ISO 4217 currency code)
  • (a) Search And Rescue
  • Special Administrative Region
  • Synthetic Aperture Radar
• SARA
  • (a) Southeastern Association for Research in Astronomy
  • Scientific Atlanta Resident Application
  • Scottish Amateur Rowing Association
  • Southern African Railway Association
  • State Administration for Religious Affairs
• SARP — (a) Search And Rescue Processor
• SARR — (i/a) Search And Rescue Repeater
• SARS — (a) Severe Acute Respiratory Syndrome
• SART
  • (a) Search and Rescue Transponder
  • Situational Awareness Rating Technique
• SARU — (i) South African Rugby Union
• SAS
  • (i) Scandinavian Airlines System
  • Second Avenue Subway
  • Situational Awareness System
  • Special Air Service
  • Studies, Analysis and Simulation
  • Side Angle Side
  • (a) Statistical Analysis System (original meaning; SAS Institute Inc. has evolved far beyond that scope)
• SASE — (i) Self-Addressed Stamped Envelope
• SASO — (a) Stability and Support Operations
• SASOL — (p) Suid Afrikaanse Steenkool en Oli.e. (Afrikaans, “South African Coal and Oil”)
• SAT
  • (i) formerly Scholastic Aptitude Test and Scholastic Assessment Test; now known solely by the initials
  • Small Arms Trainer
• SATB — (i) Soprano Alto Tenor Bass
• SATNAV — (p) Satellite Navigation (Increasingly common GPS based system in new vehicles)
• SATs — (a) Standard Assessment Tasks and other similar terms describing tests used in English schools; see National Curriculum assessment#Terminology
• SAU — (s) Saudi Arabia (ISO 3166 trigram)
• SAVAK — (a) Sazamane Etelaat va Amniate Kechvar (Iranian “Security and Intelligence Service”)
• SAW
  • (a) Squad Automatic Weapon
  • Surface acoustic wave
• SAWE — (a) Society of Allied Weight Engineers

SB

• Sb — (s) Antimony (Latin Stibium)
• SB
  • (i) Sexy Bitch
  • Sexy Bastard
  • Sexy Boy (disambiguation)
  • (s) Solomon Islands (ISO 3166 digram)
  • (i) Special Warfare Boat Operator
• SBA
  • (i) Santa Barbara Airport
  • Simulation-Based Acquisition
  • Sovereign Base Area
  • Student bar association
• SBB — (i) German for the Swiss Federal Railways
• SBC
  • (i) Sensotronic Brake Control
  • Single-Board Computer
  • Southern Baptist Convention
• SBCCOM — (p) U.S. Army Soldier and Biological Chemical Command (disbanded 2003)
• SBCS — (i) Single-Byte Character Set
• SBCT — (i) Stryker Brigade Combat Team
• SBD
  • (s) Solomon Islands dollar (ISO 4217 currency code)
  • Silent But Deadly
• SBNO – (i) Standing but not operating (in reference to amusement parks)
• SBP
  • (i) Samahang Basketbol ng Pilipinas (Filipino, "Basketball Federation of the Philippines")
  • U.S. School Breakfast Program
  • Society of Business Practitioners
  • State Bank of Pakistan
• SBS
  • (i) Special Boat Service
  • Special Broadcasting Service
  • Seoul Broadcasting System
• SBW
  • (i) Sonny Bill Williams (New Zealand dual-code rugby player)

SC

• sc — (s) Sardinian language (ISO 639-1 code)
• Sc — (s) Scandium
• SC
  • (s) Cruiser Submarine (US Navy hull classification) c Saint Kitts and Nevis (FIPS 10-4 country code; from Saint Christopher)
  • Seychelles (ISO 3166 digram)
  • South Carolina (postal symbol)
• SCA
  • (i) Service Contract Act
  • Sexual Compulsives Anonymous
  • Society for Creative Anachronism
• SCAP — (a) Supreme Commander Allied Powers (Allied occupation of Japan)
• sccm — (s) Standard cubic centimetre per minute (unit of measurement of fluid flow)
• sccs — (s) Standard cubic centimetre per second (unit of measurement of fluid flow)
• scfh — (s) Standard cubic foot per hour (unit of measurement of fluid flow)
• scfm — (s) Standard cubic foot per minute (unit of measurement of fluid flow)
• scfs — (s) Standard cubic foot per second (unit of measurement of fluid flow)
• SCG — (s) Serbia and Montenegro (ISO 3166 trigram; defunct since 2006)
• SCHIMS — (i) Soldier Combat Helmet Identification Marking System
• SCHIP — (a) State Children's Health Insurance Program (U.S.; often pronounced "ess-chip")
• SciFi — Science Fiction
• sCJD — (i) Sporadic Creutzfeldt-Jakob disease
• SCM — (i) Surface Contamination Module
• SCMODS — (s) State, County, Municipal Offender Data System
• SCN — (p) Suprachiasmatic Nucleus
• SCNT — (i) Somatic Cell Nuclear Transfer
• SCO
  • (i) Santa Cruz Operation (initials later used by SCO Group)
  • (s) Scotland (FIFA trigram; not eligible for an ISO 3166 or IOC trigram)
  • (a) Shanghai Cooperation Organization
• SCOTUS — (a) Supreme Court of the United States
• SCR — (s) Seychelles rupee (ISO 4217 currency code)
• SCRAM — (a) Safety Control Rod Axe Man
• SCS
  • (i) Scan Correlated Shift
  • Soil Conservation Service
• SCSI
  • (a) Small Computer System Interface (“scuzzy”)
  • (i) Strategic and Combat Studies Institute
• SCT — (s) Scattered Sky (METAR Code)
• SCTP — (i) Stream Control Transmission Protocol
• Scuba — (a) Self Contained Underwater Breathing Apparatus
• SCUF — Slow Continuous Ultrafiltration
• SCUFN — (i) Sub-Committee on Undersea Feature Names (of GEBCO)

SD

• sd — (s) Sindhi language (ISO 639-1 code)
• SD
  • (i) Secure Digital (memory card format)
  • Sheriff's department
  • Smoke/Decontamination
  • (s) South Dakota (postal symbol)
  • Sudan (ISO 3166 digram)
• SDC
  • (i) Shaft Driven Compressor
  • U.S. Army Strategic Defense Command (1985–1992)
• SDG — (s) Sudanese pound (ISO 4217 currency code)
• SDG — (i) Sum Dum Goy - greasy spoon chinese restaurant
• SDH — (i) Synchronous Digital Hierarchy
• SDHC – (i) Secure Digital High Capacity
• SDI — see entry
• SDN — (s) Sudan (ISO 3166 trigram)
• SDO — (i) Scattered Disc Object
• SDP — (i) Social Democratic Party (European politics)
• SDR — (i) Strategic Defence Review
• SDRAM — (i) Synchronous Dynamic Random-Access Memory (“ess-dee-ram”)
• SDS — (i) Students for a Democratic Society
• SDSS — (i) Sloan Digital Sky Survey
• SDXC – (p) Secure Digital eXtended Capacity

SE

• se — (s) Northern Sami language (ISO 639-1 code)
• Se — (s) Selenium
• SE
  • (s) Seychelles (FIPS 10-4 country code)
  • (i) Societas Europaea (form of business organization in the EU)
  • South-east
  • (s) Sweden (ISO 3166 digram)
  • (i) Synthetic Environment
  • System Engineering
• SEAD — (i) Suppression of Enemy Air Defence(s)
• SEADI — (i) Senior Executioner of Approved Driving Instructors
• SEAFDEC — (p) Southeast Asian Fisheries Development Center
• SEAL — (p) SEa-Air-Land
• SEAT — (a) Sociedad Española de Automóviles de Turismo (Spanish for "Spanish Touring Car Company")
• SEATO — (a) Southeast Asia Treaty Organization
• SeaWiFS — (p) Sea-Viewing Wide Field of View Sensor (satellite instrument)
• SEC
  • (i) U.S. Securities and Exchange Commission
  • (p) Security
  • Southeastern Conference
• SECAM — (a) Séquentiel couleur à mémoire (French for “Colour Sequential with Memory”; TV standard, cf. NTSC, PAL)
• SECDEF — (p) (U.S.) Secretary of Defense
• SED — (i) CERDEC Software Engineering Directorate
• SEDRIS — (a) Synthetic Environment Data Representation and Interchange Specification
• SEE — (a) Small Emplacement Excavator
• SEG — (i) Society of Exploration Geophysicists
• SEG — (i) Special Escort Group
• SEK — (s) Swedish krona (ISO 4217 currency code)
• Selkent — (p) South East London & Kent Bus Company
• SELT — (a) Single Ended Line Test (ing)
• SEM
  • (i/a) Sensor Employment Manager
  • Switch to Email Mode, i.e. stop texting as it is more disruptive by making a sound or vibrating and email instead, for a given time
• SEN
  • (s) Senegal (ISO 3166 trigram)
  • (i) Small Extension Node
• SEP
  • (i) Somebody Else’s Problem
  • Spherical Error Probable
  • System Enhancement Package
  • System Engineering Plan
• SEPTA — (i) Southeastern Pennsylvania Rapid-Transit Authority
• SERE — (i) Survival, Evasion, Resistance and Escape
• SESSPE — (a) Submarine Escape and Surface Survival Personnel Equipment
• SET — (p) Staphylococcal EnteroToxin
• SETI — (a) Search for ExtraTerrestrial Intelligence
• SETAC — (a) Society for Environmental Toxicology and Chemistry
• SEU
  • (i) Single Event Upset (solid state physics)
  • Slightly Enriched Uranium
  • Special Evidence Unit

SF

• SF
  • (s) Fleet Submarine (retired US Navy hull classification)
  • (i) San Francisco
  • Science fiction
  • (s) South Africa (FIPS 10-4 country code)
  • (i) Speculative fiction
  • Special Forces
• SFA
  • (i) Sales force automation
  • Saturated fatty acid
  • Scottish Football Association
  • Stephen F. Austin (State University)
  • Sudan Football Association
• SFE
  • (i) Supercritical fluid extraction
  • Sydney Futures Exchange
• SFF — (i) Standard File Format
• sf&f — (i) Science fiction & fantasy
• SFM — Switch to Facebook Mode, i.e. to message someone on Facebook instead of texting as it is less disruptive in the sense of the phone not making sound or vibrating, for a period of time
• SFOB — (i) Special Forces Operations Base
• SFOR — (p) UN Stabilisation Force (in Bosnia and Herzegovina)
• SFU — (i) Simon Fraser University (Canada)

SG

• sg — (s) Sango language (ISO 639-1 code)
• Sg — (s) Seaborgium
• SG
  • (s) Senegal (FIPS 10-4 country code)
  • Singapore (ISO 3166 digram)
  • Snow Grains (METAR Code)
  • (i) Study Group
• SGC
  • (i) Server Gated Cryptography
  • (p) Stargate Command
• SGD — (s) Singapore dollar (ISO 4217 currency code)
• SGML — (i) Standard Generalized Markup Language
• SGP — (s) Singapore (ISO 3166 trigram)
• SGS
  • (s) South Georgia and the South Sandwich Islands (ISO 3166 trigram)
  • (i) Svalbard Ground Station (Landsat)
  • Société Générale de Surveillance

SH

• sh — (s) Serbo-Croatian language (ISO 639-1 code)
• SH
  • (s) Saint Helena (ISO 3166 digram)
  • (p) SONATRACH (Algerian petroleum company)
• SHAC
  • (a) Stop Huntingdon Animal Cruelty
  • Student Health Action Coalition
• SHAPE — (a) Supreme Headquarters Allied Powers Europe
• SHF — (i) Super High Frequency
• SHN — (s) Saint Helena (ISO 3166 trigram)
• SHO – (a) Showtime (see also sho.com)
• SHOALS — (a) Scanning Hydrographic Operational Airborne Lidar Survey
• SHORAD — (p) Short Range Air Defence
• SHORADEZ — (p) SHORAD Engagement Zone
• SHP — (s) Saint Helena pound (ISO 4217 currency code)
• SHRA — (s) Rain Showers (METAR Code)
• SHSN — (s) Snow Showers (METAR Code)

SI

• si — (s) Sinhalese language (ISO 639-1 code)
• Si — (s) Silicon
• SI
  • (s) Slovenia (ISO 3166 and FIPS 10-4 country code digram)
  • (i) Socialist International
  • Sports Illustrated
  • Système International (French, International System of Units)
• SIA — (s) Singapore Airlines (ICAO code)
• SIA — (i) Survivors of Incest Anonymous
• SIAM — (i) Society for Industrial and Applied Mathematics
• SIC — (a) Standard Industrial Classification
• SICS — (a/i) Swedish Institute of Computer Science
• SIDS — (a) Sudden infant death syndrome
• SIDU — (i) select, insert, delete, update. See Create, read, update and delete
• SIF — (i) Selective Identification Feature
• SIFF — (i) Successor IFF
• SIG
  • (i) Schweizerische Industrie Gesellschaft (German, "Swiss Industry Company"). See also SIG Sauer, a firearms manufacturer spun off from the aforementioned company in 2000.
  • (p) .signature (UNIX shell/Internet standard file name)
  • (a/i) Special Interest Group
• SIGCAT — (a) Special Interest Group for CD-ROM Applications and Technology
• SIGINT — (p) Signals Intelligence
• SIGMET — (p) Significant Meteorological Information
• SIIT
  • (i) Saskatchewan Indian Institute of Technologies (Canadian university)
  • Sirindhorn International Institute of Technology (Thai university)
  • Stateless IP/ICMP Translation algorithm
• SIMAC — (a) Semantic Interaction with Music Audio Contents
• SIMLAS — (p) Soldier Integrated Multipurpose Laser System
• SIMM — (a) Single In-line Memory Module
• SIMNET — (p) SIMulator NETwork, later SIMulation NETwork
• SIMNET-D - (p) SIMNET-Developmental
• SIMP — (a) Strongly Interacting Massive Particle
• SIMPLE
  • (a) Satellite Interactive Multimedia Platform for Low-cost Earth stations
  • (p) Savings Incentive Match Plan for Employees (as used in SIMPLE IRA)
  • (a) Standard Interface for Multiple Platform Link Evaluation (NATO STANAG 5602)
• sin — (s) Sinhalese language (ISO 639-2 code)
• SIN — (a) Social Insurance Number (Canada)
• SINCGARS — (p) SINgle Channel Ground and Airborne Radio System
• SIP
  • (i) Session Initiation Protocol
  • State Implementation Plan
  • System Improvement Program
  • Systematic Investment Plan
• SIPP — (a) Self-Invested Personal Pension
• Siri – (a) Speech Interpretation and Recognition Interface (Apple iOS software)
• SIRI – (a) Service Interface for Real Time Information
• SiS — (i) Silicon Integrated Systems
• SIS — (i) UK Secret Intelligence Service (also known as MI6)
• SISO
  • (a) Simulation Interoperability Standards Organization
  • Society of Independent Show Organizers
• SIW — (i) Simulation Interoperability Workshop
• SIYSS — (i) Stockholm International Youth Science Seminar

SJ

• SJ
  • (s) Svalbard and Jan Mayen (ISO 3166 digram)
  • (i) Societas Iesu (Latin: The Society of Jesus, the Jesuit order)
  • (i) Statens Järnvägar (Swedish State Railways)
• SJA — (i) Staff Judge Advocate (military law)
• SJC — (i) Supreme Judicial Court of Massachusetts (note: the highest court in the state of Maine is also called the Supreme Judicial Court)
• SJM — (s) Svalbard and Jan Mayen (ISO 3166 trigram)

SK

• sk — (s) Slovak language (ISO 639-1 code)
• SK
  • (s) Saskatchewan (postal symbol)
  • Slovakia (ISO 3166 digram)
• SKC — (s) Clear Sky (METAR Code)
• SKK — (s) Slovak koruna (ISO 4217 currency code)
• SKM — (s) Sikkim (ISO 3166 trigram; obsolete 1975)

SL

• sl — (s) Slovene language (ISO 639-1 code)
• SL
  • (s) Sierra Leone (ISO 3166 and FIPS 10-4 country code digram)
  • (i) Start Line
• SLA
  • (i) Service Level Agreement
  • Symbionese Liberation Army
• SLAA — (i) Sex and Love Addicts Anonymous
• SLAC — (a) Stanford Linear Accelerator Center
• SLAN — (i) sine loco, anno, nomine (Latin, “without place, year, or name”)
• SLAPP — (a) Strategic lawsuit against public participation
• SLB — (s) Solomon Islands (ISO 3166 trigram)
• SLBM — (i) Sea/Submarine-Launched Ballistic Missile
• SLC — (i) Scan Line Corrector
• SLE — (s) Sierra Leone (ISO 3166 trigram)
• SLI/SLi
  • (i/s) Scan-Line Interleave
  • Scalable Link Interface
• SLIT — (p) SubLingual ImmunoTherapy
• slk — (s) Slovak language (ISO 639-2 code)
• SLL — (s) Sierra Leone leone (ISO 4217 currency code)
• SLO — (s) Slovenia (IOC trigram, but not FIFA or ISO 3166)
• SLOC
  • (a) Sea Lines Of Communication
  • Source Lines Of Code
• SLORC — (a) State Law and Order Restoration Council (of Burma)
• SLP
  • (i) Sea Level Pressure
  • (i) Super Long Play
• slph — (s) Standard litre per hour (air flow)
• slpm — (s) Standard litre per minute (air flow)
• slps — (s) Standard litre per second (air flow)
• SLR — (i) Single-Lens Reflex (camera)
• SLT
  • (i) Single Lens Translucent
  • (i) Speech and language therapist
  • (i) Solid Logic Technology (electronics)
  • Swing Landing Trainer (paratroops)
  • (i)Secondary lymphoid tissue
• slv — (s) Slovenian language (ISO 639-2 code)
• SLV — (s) El Salvador (ISO 3166 trigram)

SM

• sm — (s) Samoan language (ISO 639-1 code)
• Sm — (s) Samarium
• SM
  • (i) Sado-Masochism
  • (s) San Marino (ISO 3166 and FIPS 10-4 country code digram)
  • (i) Soldier's Manual
  • (s) Submarine Minelayer (US Navy hull classification)
• SMA — (i) Scan Mirror Assembly
• SMART — (a) Subject Matter And Requirements Team
• SMASS — (a) Small Main-Belt Asteroid Spectroscopic Survey
• SMCT — (i) Soldier's Manual of Common Tasks
• SMD — (i) Surface Mount Device
• SMDR — (i) Station Message Detail Recording
• sme — (s) Northern Sami language (ISO 639-2 code)
• SME
  • (i) Scan Mirror Electronics
  • Subject Matter Expert
• SMG
  • (i) Sequential Motorsport Gearbox
  • SubMachine Gun
• SMH — (a) Shaking My Head
• SMil — (a) Sadomasochisterne i landet (Danish SM organisation)
• SMIL — (a) Synchronized Multimedia Integration Language
• smo — (s) Samoan language (ISO 639-2 code)
• SMP — (i) Standard Military Pattern
• SM&R — (i) Source, Maintenance, and Recoverability
• SMR — (s) San Marino (ISO 3166 trigram)
• SMS — many, including: Short message service; see entry
• SMTP — (i) Simple Mail Transfer Protocol
• SMU — (i) Southern Methodist University
• SMX
  • many, including: (i) Server Macro Expansion
  • (p) Solaris MINIX
  • (p) Spatial multiplexing
  • (p) Sulfamethoxazole; see entry
• SMZ
  • many, including: (i) Silver Mt. Zion
  • (p) Sulfamethazine
  • (p) Sulfamethoxazole; see entry

SN

• sn — (s) Shona language (ISO 639-1 code)
• Sn — (s) Tin (Latin Stannum)
• SN
  • (s) Senegal (ISO 3166 digram)
  • Singapore (FIPS 10-4 country code)
  • Snow (METAR Code)
  • SuperNova
  • Screen Name
• sna — (s) Shona language (ISO 639-2 code)
• SNAFU — (a) “Situation Normal — All Fouled/Fucked Up”
• SNAP — (p) Supernova/Acceleration Probe
• SNCB — (i) Société nationale des chemins de fer de Belgique (French for “Belgian Railways National Society”, NMBS in Dutch)
• SNCF — (i) Société nationale des chemins de fer français (French for “French Railways National Society”)
• snd — (s) Sindhi language (ISO 639-2 code)
• SND — (i) Standard Nomenclature Database
• SNE — (i) Synthetic Natural Environment
• SNES — Super Nintendo Entertainment System
• SNÉTA — (a) Syndicat national pour l'étude des transports aériens (French for “Aerial transport Study National Syndicate”, 1919–1923)
• SNG — (i) Satellite News Gathering (television)
• SNL
  • (i) Saturday Night Live (television)
  • (i) Società Navigazione del Lago di Lugano
• SNM — (i) Special Nuclear Material
• SNMP — (i) Simple Network Management Protocol
• SNOBOL — (p) StriNg Oriented symBOlic Language
• SNP — (i) Single-nucleotide polymorphism
• SNR
  • (i) SuperNova Remnant
  • Signal-to-Noise Ratio
• SNRI — (i) Serotonin-Norepinephrine Reuptake Inhibitor
• SNS — (i) Spallation Neutron Source
• SNU — (i) Solar Neutrino Unit

SO

• so — (s) Somali language (ISO 639-1 code)
• SO
  • (i) Shared Object (Unix)
  • Sheriff's Office
  • Significant other
  • (s) Somalia (ISO 3166 and FIPS 10-4 country code digram)
• SOA
  • (a) service-oriented architecture
  • (a) Society of Actuaries
  • (i) State of the art
• SOAP
  • (a) Simple Object Access Protocol
  • Supplemental Offer and Acceptance Program (U.S. medical residency matching)
• SOB
  • (i) Son Of a Bitch
  • Same Old Bullshit
• SOC — (a) Sector Operations Centre
• SOCCSKSARGEN — (p) South Cotabato, Cotabato, Sultan Kudarat, Sarangani, General Santos City (a region in the Philippines; pronounced “sock-sar-gen”)
• SOCOM — (p) (U.S.) Special Operations Command
• SoCon – (p) Southern Conference (U.S. college sports)
• SOD
  • (i/a) School Of Dentistry
  • Statement Of Difference[s]
  • Statement Of Direction
  • Statement Of Documentation
  • Statement Of Duty/Duties
• SOE
  • (i) Secret Of Evermore
  • Special Operations Executive (WWII British organization)
  • State Of Emissions (EW)
• SOF
  • (a/i) Special Operations Force(s)
  • Status of Forces
• SOFIA — (a) Stratospheric Observatory For Infrared Astronomy
• SOGAT
  • (a) Society of Graphical and Allied Trades
  • Former British printing union
• SOHC — (i) Single-OverHead-Cam engine
• SOHO — (p) Solar and Heliospheric Observatory
• SOI — (i) Signal Operating Instruction
• SOL — (i) Shit Out of Luck
• SOLIS — (i) Synoptic Optical Long-term Investigations of the Sun
• som — (s) Somali language (ISO 639-2 code)
• SOM
  • (a) Simulation Object Model
  • (s) Somalia (ISO 3166 trigram)
• Sonar — (p) SOund Navigation And Ranging
• SOP
  • (i) Standing/Standard Operating Procedure
  • State of Play
• SOR
  • (i) State Of Readiness
  • Statement Of Requirements
• SOS
  • (s) Somali shilling (ISO 4217 currency code)
  • Save Our Souls
• SOSTAR — (a) Stand-Off Surveillance and Target Acquisition Radar
• sot — (s) Sotho language (ISO 639-2 code)
• SOUTHAG — (p) Southern Army Group
• SOUTHCOM — (p) (U.S.) Southern Command
• SOV — (i) Single Occupant Vehicle
• SOW — (i) Statement Of Work
• SOWHAT — (p) RESNA Subcommittee on Wheelchairs and Transportation
• SOX — (p) Sarbanes–Oxley Act

SP

• Sp
  • (p) Special
  • Spring tide (nautical charts)
  • (i) sine prole (Latin, “without offspring”)
• SP
  • (i) Security Police
  • Self-Propelled
  • Shore Patrol
  • (s) Spain (FIPS 10-4 country code)
  • (i) Start Point
  • Strong Point
• spa — (s) Spanish language (ISO 639-2 code)
• SPAAG — (a) Self-Propelled Anti-Aircraft Gun
• SPACECOM — (p) (U.S.) Space Command
• Spaser — (a) Surface plasmon amplification by stimulated emission of radiation
• SPC — (i) Secretariat of the Pacific Community
• SPCO — (i) Single-Pole Change Over
• SPD
  • (i) Shimano Pedaling Dynamics
  • Sozialdemokratische Partei Deutschlands (Social Democratic Party of Germany)
• SPDT — (i) Single-Pole Double-Throw
• SPEAC — (a) Stop Primate Experiments at Cambridge (later became SPEAK)
• SPECTRE — SPecial Executive for Counter-intelligence, Terrorism, Revenge and Extortion
• SPEED — (a) Subsistence Preparation by Electronic Energy Diffusion (early military microwave oven)
• SPIE — (i) originally the Society for Photo-Optical Instrumentation Engineers (“SPIE — The International Society for Optical Engineering” 1981–2007, “SPIE” since 2007)
• SPL
  • (i) Scottish Premier League
  • Superior Parietal Lobule
  • Sound Pressure Level
• SPM — (s) Saint Pierre and Miquelon (ISO 3166 trigram)
• SPOD — (a/i) Sea Port of Debarkation
• SPOE — (a/i) Sea Port of Embarkation
• SPOT — (a) Satellite pour l'observation de la Terre (French, “Satellite for Earth Observation”)
• SPQR — (i) Senatus Populusque Romanus (Latin “The Senate and the People of Rome”)
• sps — (i) sine prole superstite (Latin, “without surviving issue”)
• SPS — (i) Standard Positioning Service (GPS)
• SPST — (i) Single-Pole Single-Throw

SQ

• sq — (s) Albanian language (ISO 639-1 code)
• SQ — (i) Sound Quality
• SQ — (i) Standard Quality
• sqi — (s) Albanian language (ISO 639-2 code)
• SQL — (i/a) Structured Query Language (“seek-well”)
• SQUID — (p) Superconducting QUantum Interference Device

SR

• sr — (s) Serbian language (ISO 639-1 code)
• Sr — (s) Strontium
• SR
  • (i) Sound Reinforcement
  • Supply Route
  • (s) Suriname (ISO 3166 digram)
  • (i) Sveriges Radio (Swedish Radio Ltd)
• SR — (i) Sustained release of a drug
• SRAM
  • (p) Scott (King), Ray (Day), SAM (Patterson) — founders of bicycle component manufacturer SRAM Corporation
  • (p) Static Random Access Memory (“ess-ram”)
• SR-ATGW — (i) Short-Range Anti-Tank Guided Weapon
• SRB — (i) Solid Rocket Booster
• SRBM — (i) Short-Range Ballistic Missile (cf. IRBM, ICBM)
• SRC — (i) Scheduled Removal Component
• srd — (s) Sardinian language (ISO 639-2 code)
• SRD
  • (i) Science Requirements Document
  • (s) Surinam dollar (ISO 4217 currency code)
• SREL — (i) Savannah River Ecology Laboratory
• SRG
  • (i) SACEUR Rover Group
  • Special Republican Guard
• SRGW — (i) Short-Range Guided Weapon
• SRL
  • (i) Savannah River Laboratory
  • Single Rocket Launcher
  • Survival Research Labs
• SRM — (i) Specified Risk Material(s)
• srp — (s) Serbian language (ISO 639-2 code)
• SRS — (i) Savannah River Site
• SRSP — (i) Science and Religion in Schools Project
• SRTP — (i) [Secure Real-time Transport Protocol]

SS

• ss — (s) Swati language (ISO 639-1 code)
• SS
  • (s) Sand Storm (METAR Code)
  • (p) Schutzstaffel (German, roughly "Protection Squadron"; Nazi elite Praetorian guard)
  • (i) U.S. Secret Service
  • Spanish Ship
  • Stainless steel
  • Stockholm Skins
  • (s) Submarine (US Navy hull classification)
  • (i) Super Sport
  • Surface-to-Surface (missile)
• SSA
  • (s) Cargo Submarine (US Navy hull classification)
  • (i) Social Security Administration (U.S.)
  • Statistics South Africa
• SSB — (a) Single-sideband modulation
• SSB — (i) Sacramento Sustainable Business
• SSBN — (s) Nuclear-Powered Ballistic Missile Submarine (US Navy hull classification)
• SSC
  • (i) Safe, Sane, Consensual (SM phrase)
  • Secondary Somatosensory Cortex
  • Smaller-Scale Contingency
  • U.S. Army Soldiers System Center (Natick, Massachusetts)
  • Superconducting Super Collider
• SSCCATAGAPP — Singles, Seniors, Childless Couples, And Teens And Gays Against Parasitic Parents (fictional organization from The Simpsons)
• SSD
  • (i) Solid-state drive
  • (s) South Sudan (ISO 3166 trigram)
• SSDC — (i) U.S. Space and Strategic Defense Command
• SSDD
  • (i) Same Shit, Different Day
  • Single-Sided Double-Density (floppy disk)
• SSE
  • (s) South South-East
  • (i) Streaming SIMD Extensions
• SSG — (s) Guided Missile Submarine (retired US Navy hull classification)
• SSGN — (s) Nuclear-Powered Guided Missile Submarine (US Navy hull classification)
• SSH — (i) Saffir-Simpson Hurricane scale
• SSK — (s) Hunter-Killer Submarine (retired US Navy hull classification)
• SSKP — (i) Single-Shot Kill Probability
• SSL — (i) Secure Sockets Layer
• SSM — (i) Surface-to-Surface (Guided) Missile
• SSN
  • (s) Nuclear-Powered Attack Submarine (US Navy hull classification)
  • (i) SIM Serial Number
  • Social Security Number (U.S.)
  • Socialist Solidarity Network
  • Subsystem number (SCCP, SS7)
• SSNW — (i) Same Shit, New Wrapping
• SSO — (s) Submarine Oiler (retired US Navy hull classification)
• SSP — (s) Submarine Transport (retired US Navy hull classification)
• SSR
  • (s) Radar Picket Submarine (retired US Navy hull classification)
  • (i) Solid State Recorder
• SSRI
  • (i) Selective Serotonin Reuptake Inhibitor
  • Social Systems Research Institute
• SSRN
  • (i) Social Science Research Network
  • (s) Nuclear-Powered Radar Picket Submarine (retired US Navy hull classification)
• SSS
  • (i) Siding Spring Survey
  • Side Side Side (an acronym for remembering congruent triangles)
  • (i) Sigue Sigue Sputnik (band)
• S/SSM — (i) Surface-to-Subsurface Missile
• SST
  • (i) SuperSonic Transport
  • (s) Training Submarine (US Navy hull classification)
  • Saturated Suction Temperature (refrigeration cycles)
• SSTO — (i) Single-Stage To Orbit
• SSV — (i) Soft-Skinned Vehicle (i.e., unarmoured)
• ssw — (s) Swati language (ISO 639-2 code)
• SSW — (s) South South-West

ST

• st — (s) Sotho language (ISO 639-1 code)
• ST
  • (s) Saint Lucia (FIPS 10-4 country code)
  • São Tomé and Príncipe (ISO 3166 digram)
• STA
  • (i) Scheduled Time of Arrival
  • Surveillance and Target Acquisition
• STAG — (a) (U.S.) Strategy and Tactics Group
• STAGE — (a) Scenario Toolkit And Generation Environment
• STANAG — (p) (NATO) Standardisation Agreement
• STAR
  • (a) Scientific and Technical Aerospace Reports (NASA)
  • Simulation of Tactical Alternative Responses
  • Special Threat Analysis and Recognition
• STAT
  • (a) Signal Transducers and Activators of Transcription (cell biology)
  • Special Tertiary Admissions Test (Australia)
• STB - Surface Transportation Board
• STC — (i) Superior Temporal Cortex
• S&TCD — (i) CERDEC Space and Terrestrial Communications Directorate
• STD
  • (s) São Tomé and Príncipe dobra (ISO 4217 currency code)
  • (i) Sexually Transmitted Disease
• STDM — (i) Statistical Time Division Multiplexing
• STENTOR — (p) Satellite de télécommunications pour expérimenter de nouvelles technologies en orbite (French, “Orbital New Technology Experimental Telecommunications Satellite”)
• STFU
  • (i) Southern Tenant Farmers Union
  • Stuff You
• STH — Sonic The Hedgehog
• STI
  • (i) Sexually Transmitted Infection
  • Subaru Tecnica International
• STK — (i) Satellite Tool Kit
• STM — (i) Short Term Memory
• STOL — (i) Short Take-Off and Landing
• STOVL — (i) Short Take-Off and Vertical Landing
• STP
  • (s) São Tomé and Príncipe (ISO 3166 trigram)
  • (i) Standard Temperature and Pressure
• STR — (i) Short Tandem Repeat (DNA analysis)
• STRATCOM — (p) United States Strategic Command
• STRICOM
  • (p) U.S. Army Simulation, Training & Instrumentation Command (1992–)
  • Strike Command (1962–1971)
• STRIVE — (a) Synthetic Tactical Real-time Interactive Virtual Environment
• STSM — (i) Senior Technical Staff Member
• Stuka — (p) Sturzkampfflugzeug (German WWII dive bomber)

SU

• su — (s) Sundanese language (ISO 639-1 code)
• SU
  • (s) Soviet Union (ISO 3166 digram; obsolete 1992)
  • Sudan (FIPS 10-4 country code)
• SUB — (i) Student Union Building
• SuD — (a) Subject under Discussion
• SUDC — Swedish United Dawah Center, a salafist Islamic organisation in Sweden
• SUI
  • (a) Sonic user interface
  • (s) Switzerland (IOC and FIFA trigram, but not ISO 3166)
• SUK — Start Up Kit
• sun — (s) Sundanese language (ISO 639-2 code)
• SUN — (s)
  • Soviet Union (ISO 3166 trigram; obsolete 1992)
  • Stanford University Network that led to Sun Microsystems
• SUNY — (a) State University of New York (usually pronounced “sue-knee”)
• SUR — (s) Suriname (ISO 3166 trigram)
• SURTASS — (p) Surveillance Towed Array Sensor System
• SUSAT — (a) Sight Unit Small Arms, Trilux
• SUV — (i) Sport Utility Vehicle

SV

• sv — (s) Swedish language (ISO 639-1 code)
• SV
  • (s) El Salvador (ISO 3166 digram)
  • (p) Sportverein (German for “Sport Association”, as in Hamburger SV and SV Werder Bremen)
• SVC — (i) Secondary Visual Cortex
• SvD — (p) Svenska Dagbladet (Swedish newspaper)
• SVD
  • (i) Singular Value Decomposition
  • Snaiperskaya Vintovka Dragunova (Снайперская винтовка Драгунова, Russian for “Dragunov Sniper Rifle”)
• SVG — (i) Scalable Vector Graphics
• SVK — (s) Slovakia (ISO 3166 trigram)
• SVM — (i) Support Vector Machine (artificial intelligence)
• SVN — (s) Slovenia (ISO 3166 and FIFA trigram)
• SVO — (i) subject–verb–object
• SVR — (i) Sluzhba Vneshney Razvedki (Служба Внешней Разведки, Russian for "Foreign Intelligence Service")

SW

• sw — (s) Swahili language (ISO 639-1 code)
• SW
  • (s) South-West ordinal direction
  • Sweden (FIPS 10-4 country code)
  • (a) Shortwave
• swa — (s) Swahili language (ISO 639-2 code)
• SWA
  • (i/a) Secure Web Access
  • South-West Asia
• SWAC — (p) Southwestern Athletic Conference
• SWALK — (a) Sealed With A Loving Kiss
• SWAN — (a) System for Wearable Audio Navigation
• SWAP — (a) Surface Waters Acidification Programme
• SWAPO — (a) South-West Africa People's Organisation
• SWAT — (a) Special Weapons And Tactics
• swe — (s) Swedish language (ISO 639-2 code)
• SWE — (s) Sweden (ISO 3166 trigram)
• SWF
  • (p) Shockwave Flash file (“swiff”)
  • Single White Female
• SWG
  • (i) Surface Warfare Group
  • Symbology Working Group
• SWHR — (i) Society for Women's Health Research
• SWIG — (a) Simplified Wrapper and Interface Generator
• SWIR — (a/i) Short Wave InfraRed (“ss-why-are” or “swhirr”)
• SWLABR
  • (i) She Was Like A Bearded Rainbow
  • Cream song (Bruce, Clapton and Baker)
• SWORD — (p) Subjective WORkload Dominance
• SWORDS — (a) Special Weapons Observation Reconnaissance Detection System
• SWOT — (a) Strengths, Weaknesses, Opportunities, Threats (mnemonic)
• SWP
  • (i) Special Working Party (“swipp”)
  • Systematic Westing Plan (a plan of periodic westing of shares or mutual funds worth a fixed amount of money)
  • Skill With Prizes (UK pub quiz machines — quality titles include: Pub Quiz, Quiz City, Frog in a Liquidizer, Who Wants To Win a Tenner?)
• SWT — (i) Sea Water Tank
• SWV — (i) Sisters With Voices (American female R&B vocal group)
• SWZ — (s) Swaziland (ISO 3166 trigram)

SX

• SX — (i) Sonic X
• SXM
  • (i) Scanning X-ray Microscope
  • (s) Sint Maarten (ISO 3166 trigram)
  • (i) Stream X-Machine

SY

• SY — (s) Syria (ISO 3166 and FIPS 10-4 country code digram)
• SYC — (s) Seychelles (ISO 3166 trigram)
• SYLK — Microsoft 'Symbolic Link' data file format
• SYP — (s) Syrian pound (ISO 4217 currency code)
• SYR — (s) Syria (ISO 3166 trigram)
• Syriza — (p) Synaspismós Rizospastikís Aristerás (Greek Συνασπισμός Ριζοσπαστικής Αριστεράς,"Coalition of the Radical Left")
• SysML — (p) System Modeling Language
• Sysop — (p) System Operator

SZ

• SZ
  • (s) Swaziland (ISO 3166 digram)
  • Switzerland (FIPS 10-4 country code)
• SZL — (s) Swaziland lilangeni (ISO 4217 currency code)