Uk (Cyrillic)

Cyrillic letter Uk
Numeric value:	400
The Cyrillic script
Slavic letters
А Б В Г Ґ Д Ђ Ѓ Е Ѐ Ё Є Ж З З́ Ѕ И Ѝ І Ї Й Ј К Л Љ М Н Њ О П Р С С́ Т Ћ Ќ У Ў Ф Х Ц Ч Џ Ш Щ Ъ Ы Ь Э Ю Я
Non-Slavic letters
Ӑ А̄ А̊ А̃ Ӓ Ӓ̄ Ә Ә́ Ә̃ Ӛ Ӕ Ғ Г̧ Г̑ Г̄ Ҕ Ӻ Ӷ Ԁ Ԃ Ꚃ Ꚁ Ꚉ Ԫ Ԭ Ӗ Е̄ Е̃ Ё̄ Є̈ Ӂ Җ Ꚅ Ӝ Ԅ Ҙ Ӟ Ԑ Ԑ̈ Ӡ Ԇ Ӣ И̃ Ҋ Ӥ Қ Ӄ Ҡ Ҟ Ҝ Ԟ Ԛ Ӆ Ԯ Ԓ Ԡ Ԉ Ԕ Ӎ Ӊ Ң Ԩ Ӈ Ҥ Ԣ Ԋ О̆ О̃ О̄ Ӧ Ө Ө̄ Ӫ Ҩ Ԥ Ҧ Р̌ Ҏ Ԗ Ҫ Ԍ Ꚑ Ҭ Ꚋ Ꚍ Ԏ У̃ Ӯ Ӱ Ӱ́ Ӳ Ү Ү́ Ұ Х̑ Ҳ Ӽ Ӿ Һ Ԧ Ꚕ Ҵ Ꚏ Ҷ Ӵ Ӌ Ҹ Ꚓ Ꚗ Ꚇ Ҽ Ҿ Ы̆ Ы̄ Ӹ Ҍ Э̆ Э̄ Э̇ Ӭ Ӭ́ Ӭ̄ Ю̆ Ю̈ Ю̈́ Ю̄ Я̆ Я̄ Я̈ Ԙ Ԝ Ӏ
Archaic letters
Ꙁ Ꙃ Ꙅ Ꙇ Ꙉ Ҁ Ѻ ОУ Ꙋ Ѡ Ѽ Ꙍ Ѿ Ꙏ Ѣ Ꙑ Ꙓ Ꙕ Ꙗ Ѥ Ѧ Ꙙ Ѫ Ꙛ Ѩ Ꙝ Ѭ Ѯ Ѱ Ѳ Ѵ Ѷ Ꙟ Ꙡ Ꙣ Ꙥ Ꙧ Ꙩ Ꙫ Ꙭ ꙮ Ꚙ Ꚛ
List of Cyrillic letters Cyrillic digraphs

Uk (Ѹ ѹ; italics: Ѹ ѹ) is a digraph of the early Cyrillic alphabet, although commonly considered and used as a single letter. It is a combination of the Cyrillic letters О and У or less frequently O and Ѵ. To save space, it was often written as a vertical ligature (Ꙋ ꙋ), called "monograph Uk". In modern times, ⟨оу⟩ has been replaced by the simple ⟨у⟩.

Borrowing from Greek

Both the horizontal and the vertical digraph were borrowed from the Greek alphabet. The Greek ligature Ou (Ȣ ȣ) is frequently found in Greek medieval manuscripts and in some modern editions of classical texts. Modern Greek still uses ⟨ου⟩ (omicron-upsilon) for /u/ but rarely uses the vertical ligature.

Development of the use of Uk in Old East Slavic

Uk (Monogram)

The simplification of the digraph ⟨оу⟩ to ⟨у⟩ was first brought about in Old East Slavic texts and only later taken over into South Slavic languages.

One can see this development in the Novgorod birch-bark letters: The degree to which this letter was used here differed in two positions: in word-initial position or before a vowel (except for the jers), and after a consonant.

Before a consonant, ⟨оу⟩ was used 89% of the time in the writings before 1100. By 1200, it was used 61% of the time, with the letter ⟨у⟩ used 14% of the time; by 1300, оу had reached 28%, surpassed by ⟨у⟩ at 45%. From the late 14th century on, there are no more instances of ⟨оу⟩ being used in this position, with ⟨у⟩ appearing 95% of the time.

The decrease in usage was more gradual after a consonant. Although there are no instances of the use of ⟨у⟩ in this position before c. 1200, ⟨оу⟩ gradually decreased from 88% before 1100 to 57% by 1200. The frequency of ⟨оу⟩ remained steady between 47% and 44% until 1400, when it experienced another decrease to 32%. Meanwhile, the use of ⟨у⟩ increased from 4% in the early 13th century, to 20% by the mid-13th century, 38% by the mid 14th century, and 58% by the early 15th century.

Representation on computers

The letter Uk was first represented in Unicode 1.1.0 as U+0478 and 0479, CYRILLIC CAPITAL/SMALL LETTER UK (Ѹ ѹ). It was later recognized that the glyph to be used for the letter had not been adequately specified, and it had been represented as either a digraph or monograph letter in different released fonts. There was also the difficulty that in written texts the letter may appear in lowercase (оу), uppercase (Оу), or in all caps (ОУ), which was not allowed for.

To resolve this ambiguity, Unicode 5.1 has deprecated the use of the original code points, introduced the new U+A64A and A64B, CYRILLIC CAPITAL/SMALL LETTER MONOGRAPH UK (Ꙋ ꙋ), and recommends composing the digraph with two individual characters ⟨о⟩+⟨у⟩ .

However, the recommended method may cause some text representation problems. The letter У did not originally appear alone in the Old Church Slavonic orthography, and thus its code point was replaced in different Old Slavonic computer fonts with digraph or monograph forms of the Uk or with the tailed form of Izhitsa. Tailed Izhitsa may be used as a part of the digraph, but using the shape of the monograph Uk as a part of the digraph Uk (оꙋ) is incorrect.

The minuscule monograph Uk was used in the Romanian Transitional Alphabet to represent /u/, but due to font restrictions, the Ȣ ligature or Latin gamma are occasionally used instead.

Computing codes

Character	О		о		У		у		Ѹ		ѹ		Ꙋ		ꙋ
Unicode name	CYRILLIC CAPITAL LETTER O		CYRILLIC SMALL LETTER O		CYRILLIC CAPITAL LETTER U		CYRILLIC SMALL LETTER U		CYRILLIC CAPITAL LETTER UK		CYRILLIC SMALL LETTER UK		CYRILLIC CAPITAL LETTER MONOGRAPH UK		CYRILLIC SMALL LETTER MONOGRAPH UK
Encodings	decimal	hex	decimal	hex	decimal	hex	decimal	hex	decimal	hex	decimal	hex	decimal	hex	decimal	hex
Unicode	1054	U+041E	1086	U+043E	1059	U+0423	1091	U+0443	1144	U+0478	1145	U+0479	42570	U+A64A	42571	U+A64B
UTF-8	208 158	D0 9E	208 190	D0 BE	208 163	D0 A3	209 131	D1 83	209 184	D1 B8	209 185	D1 B9	234 153 138	EA 99 8A	234 153 139	EA 99 8B
Numeric character reference	О	О	о	о	У	У	у	у	Ѹ	Ѹ	ѹ	ѹ	Ꙋ	Ꙋ	ꙋ	ꙋ

Further reading

• Kaplan, Michael S. “Every character has a story #10: U+0478/U+0479 (CYRILLIC LETTER UK)”, May 21, 2005.
• Zaliznyak, Andrey (2004). Drevnenovgorodskij dialekt. Moscow: Jazyki slavjanskoj kul'tury.