Ou (ligature)

Ou (Majuscule: Ȣ, Minuscule: ȣ) is a ligature of the Greek letters ο and υ which was frequently used in Byzantine manuscripts. This ligature is still seen today on icon artwork in Greek Orthodox churches, and sometimes in graffiti or other forms of informal or decorative writing.

The ligature is now mostly used in the context of the Latin alphabet, interpreted as a ligature of Latin o and u: for example, in the orthography of the Wyandot language and of Algonquian languages of Western Abenaki to represent /ɔ̃/, and in Algonquin to represent /ɯ/. Today, in Western Abenaki, "ô" is preferred, and in Algonquin, "w" is preferred.

The ligature, in both majuscule and minuscule forms, is occasionally used to represent minuscule оf "У" in the Romanian Transitional Alphabet, as the glyph for monograph Uk (ꙋ) is rarely available in font sets.

The same ligature was also used in the context of Cyrillic; see Uk (Cyrillic).

In Unicode, it is encoded for use in Latin as "Latin Capital Script OU" (U+0222 Ȣ) and "Latin Small Letter OU" (U+0223, ȣ) in the Latin Extended-B range, and for use in Cyrillic as Cyrillic letter monograph Uk (uppercase U+A64A, Ꙋ, lowercase U+A64B, ꙋ), in addition to now deprecated "Cyrillic letter Uk" (uppercase U+0478, Ѹ, lowercase U+0479, ѹ), which may be realized with the "о" and "у" either side by side or combined vertically.

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