Colon (letter)

Several of the Native American languages of North America use the colon (U+003A : COLON) to indicate vowel length. Zuni is one. Other languages include Hupa of California, Oʼodham of Arizona, Sayula Popoluca of Mexico and Mohawk of Ontario. Still others use a half colon (just the top dot of the colon, or a middot, U+00B7 · MIDDLE DOT, not to be confused with U+A78F ꞏ LATIN LETTER SINOLOGICAL DOT or other dot characters). Both conventions derive from Americanist phonetic notation (below).

The letter colon (U+A789 ꞉ MODIFIER LETTER COLON) distinct from and generally smaller than the punctuation colon, is used as a grammatical tone letter in Budu in the Democratic Republic of the Congo, in Sabaot in Kenya, and in some Grebo in Liberia. It is also used in several languages of Papua New Guinea: Erima, Gizra, Go꞉bosi, Gwahatike, Kaluli, Kamula, Kasua, Kuni-Boazi and Zimakani.

In Erima, the letter colon is used before a vowel letter a or u to indicate nasalization, for example h꞉aambi "yam", ꞉uwai "a bee".

In Gizra, the letter colon is used in the digraph u꞉ /ɨ/ distinct from the letter u /u/. The digraph doesn’t often occur at the end of words, but is still distinct from a word ending with u followed by the punctuation colon.

In Go꞉bosi, the letter colon is used as a diacritic to distinguish o꞉ /o/ from o /ɔ/.

In Kaluli, the letter colon is used as a diacritic to distinguish a꞉ /ɛ/ from a /a/, and o꞉ /ɔ/ from o /o/.

In Kamula, the letter colon is used as a diacritic to distinguish a꞉ /ɛ/ from a /a/.

In Kasua, the letter colon is used as a diacritic to distinguish a꞉ /æ/ from a /ɑ/.

In Kuni-Boazi the letter colon is used after a vowel letter to indicate grammatical vowel lengthening, for example gemanqatam "when he talked" and ge꞉manqatam "when he talked about it"..

In Americanist phonetic notation, a colon may be used to indicate vowel length. This convention is somewhat less common than the half-colon.

In the International Phonetic Alphabet, a triangular or trapezoidal colon-like letter is used to indicate that the preceding consonant or vowel is long. Its form is that of two triangles or trapezoids pointing toward each other rather than the two dots of Americanist notation. It is available in Unicode as U+02D0 ː MODIFIER LETTER TRIANGULAR COLON. If the upper triangle is used without the lower one (U+02D1 ˑ MODIFIER LETTER HALF TRIANGULAR COLON), it designates a half-long vowel or consonant.

The Uralic Phonetic Alphabet uses U+02F8 ˸ MODIFIER LETTER RAISED COLON.