Mater lectionis

In the spelling of Arabic and some other Semitic languages, matres lectionis (/ˈmeɪtriːz lɛktiˈoʊnᵻs/; from Latin "mothers of reading", singular form: mater lectionis, Hebrew: אֵם קְרִיאָה 'em k'ri'á), refers to the use of certain consonants to indicate a vowel. In Arabic, the matres lectionis (though they are much less often referred to thus) are alif ا, waw و, and ya' ي. The letters that do this in Hebrew are א aleph, ה he, ו waw (or vav) and י yod (or yud). The yod and waw in particular are more often vowels than they are consonants.

History

Because the scripts used to write some Semitic languages lack vowel letters, unambiguous reading of a text might be difficult. Therefore, to indicate vowels (mostly long), consonant letters are used. For example, in the Hebrew construct-state form bēt, meaning "the house of", the middle letter "י" in the spelling בית acts as a vowel, whereas in the corresponding absolute-state form bayit ("house"), which is spelled the same, the same letter represents a genuine consonant. Matres lectionis are found in Ugaritic, Moabite, South Arabian and the Phoenician alphabets, but are widely used only in Arabic, Aramaic, Syriac and Hebrew.