Kamatz

Qamatz (Hebrew: קָמַץ‎, IPA: [kaˈmats]) is a Hebrew niqqud (vowel) sign represented by two perpendicular lines (looking like an uppercase T) ⟨ ָ ‎ ⟩ underneath a letter. In modern Hebrew (Sephardi/Israeli), it usually indicates the phoneme /a/ which is close to the "a" sound in the English word far and is transliterated as a  and thus its sound is identical to the sound of pataḥ  in modern Hebrew. In some cases it indicates the phoneme /o/, equal to the sound of ḥolam.

The Hebrew of the late centuries BCE and early centuries of the Common Era had a system with five phonemic long vowels /aː eː iː oː uː/ and five short vowels /a e i o u/. In the later dialects of the 1st millennium, phonemic vowel length disappeared, and instead was automatically determined by the context, with vowels pronounced long in open syllables and short in closed ones. However, the previous vowel phonemes merged in various ways that differed from dialect to dialect. In Tiberian Hebrew, which underlies the written system of vowels, short /a/ became [a] (indicated by pataḥ); long /oː/ became [o] (indicated by ḥolam); while /aː/ and /o/ both merged into an in-between sound [ɔ] (similar to the vowel in English "caught"), which was indicated by qamatz. In the Babylonian vocalization, however, short and long variants simply merged, with /a/ and /aː/ becoming [a], while /o/ and /oː/ became [o]; and this system underlies the pronunciation of Modern Hebrew.

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