Ou (Majuscule: , Minuscule: ) is a

ligature Ligature may refer to: * Ligature (medicine), a piece of suture used to shut off a blood vessel or other anatomical structure ** Ligature (orthodontic), used in dentistry * Ligature (music), an element of musical notation used especially in the me ...

of the

Greek letters The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BCE. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as w ...

ο and υ which was frequently used in

Byzantine The Byzantine Empire, also referred to as the Eastern Roman Empire or Byzantium, was the continuation of the Roman Empire primarily in its eastern provinces during Late Antiquity and the Middle Ages, when its capital city was Constantinopl ...

manuscripts. This ligature is still seen today on

icon An icon () is a religious work of art, most commonly a painting, in the cultures of the Eastern Orthodox, Oriental Orthodox, and Catholic churches. They are not simply artworks; "an icon is a sacred image used in religious devotion". The most ...

artwork in Greek Orthodox churches, and sometimes in

graffiti Graffiti (plural; singular ''graffiti'' or ''graffito'', the latter rarely used except in archeology) is art that is written, painted or drawn on a wall or other surface, usually without permission and within public view. Graffiti ranges from s ...

or other forms of informal or decorative writing.

Usage

The ligature is now mostly used in the context of the

Latin alphabet The Latin alphabet or Roman alphabet is the collection of letters originally used by the ancient Romans to write the Latin language. Largely unaltered with the exception of extensions (such as diacritics), it used to write English and the o ...

, interpreted as a ligature of Latin o and u: for example, in the orthography of the

Wyandot language Wyandot (sometimes spelled Wandat) is the Iroquoian language traditionally spoken by the people known variously as Wyandot or Wyandotte, descended from the Tionontati. It is considered a sister to the Wendat language, spoken by descendants of the ...

and of

Algonquian languages The Algonquian languages ( or ; also Algonkian) are a subfamily of Indigenous languages of the Americas, indigenous American languages that include most languages in the Algic languages, Algic language family. The name of the Algonquian language f ...

e.g. in

Western Abenaki The Abenaki (Abenaki language, Abenaki: ''Wαpánahki'') are an Indigenous peoples of the Northeastern Woodlands of Canada and the United States. They are an Algonquian languages, Algonquian-speaking people and part of the Wabanaki Confederacy. ...

to represent , and in

Algonquin Algonquin or Algonquian—and the variation Algonki(a)n—may refer to: Languages and peoples *Algonquian languages, a large subfamily of Native American languages in a wide swath of eastern North America from Canada to Virginia **Algonquin la ...

to represent , or . Today, in Western Abenaki, "ô" is preferred, and in Algonquin, "w" is preferred. An ou ligature much different in form (with the two letters side-by-side as in most ligatures, as opposed to one on top of the other) was used in the

Initial Teaching Alphabet The Initial Teaching Alphabet (I.T.A. or i.t.a.) is a variant of the Latin alphabet developed by Sir James Pitman (the grandson of Sir Isaac Pitman, inventor of a system of shorthand) in the early 1960s. It was not intended to be a strictly phonet ...

. The ligature, in both majuscule and minuscule forms, is occasionally used to represent minuscule of "У" in the

Romanian Transitional Alphabet The Romanian transitional alphabet ( ro, Alfabetul român de tranziție), also known as the civil alphabet ( ro, alfabetul civil), was a series of alphabets containing a mix of Cyrillic and Latin script, Latin characters used for the Romanian la ...

, as the glyph for monograph Uk (ꙋ) is rarely available in font sets. Wabikoni

The

Uralic Phonetic Alphabet The Uralic Phonetic Alphabet (UPA) or Finno-Ugric transcription system is a phonetic transcription or notational system used predominantly for the transcription and reconstruction of Uralic languages. It was first published in 1901 by Eemil Nesto ...

uses and to indicate a

back vowel A back vowel is any in a class of vowel sound used in spoken languages. The defining characteristic of a back vowel is that the highest point of the tongue is positioned relatively back in the mouth without creating a constriction that would be c ...

of unknown quality.

Computer encoding

Unicode Unicode, formally The Unicode Standard,The formal version reference is is an information technology Technical standard, standard for the consistent character encoding, encoding, representation, and handling of Character (computing), text expre ...

, 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 , bg, кирилица , mk, кирилица , russian: кириллица , sr, ћирилица, uk, кирилиця , fam1 = Egyptian hieroglyphs , fam2 = Proto-Sinaitic , fam3 = Phoenician , fam4 = Gr ...

(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. Despite the ligature's origin in Greek, there is no separate provision for its encoding in the Greek script, because it was deemed to be a mere ligature on the font level but not a separate underlying character. A proposal for encoding it as "Greek letter ou" was made in 1998, but was rejected.Nick Nicholas
Other ligatures
'.

References

{{Latin script Ou Ou Vowel letters