An abugida /ˌɑːbʊˈɡiːdə/ (from Ge'ez: አቡጊዳ ’abugida), or alphasyllabary, also known as avugida, is a segmental writing system in which consonant–vowel sequences are written as a unit: each unit is based on a consonant letter, and vowel notation is secondary. This contrasts with a full alphabet, in which vowels have status equal to consonants, and with an abjad, in which vowel marking is absent, partial, or optional. (In less formal contexts, all three types of script may be termed alphabets.) The terms also contrast them with a syllabary, in which the symbols cannot be split into separate consonants and vowels. Abugidas include the extensive Brahmic family of scripts of South and Southeast Asia, Semitic Ethiopic scripts, and Canadian Aboriginal syllabics (which are themselves based in part on Brahmic scripts).
As is the case for syllabaries, the units of the writing system may consist of the representations both of syllables and of consonants. For scripts of the Brahmic family, the term akshara is used for the units.
Abugida as a term in linguistics was proposed by Peter T. Daniels in his 1990 typology of writing systems.’Äbugida is an Ethiopian name for the Ge‘ez script, taken from four letters of that script, 'ä bu gi da, in much the same way that abecedary is derived from Latin a be ce de, abjad is derived from the Arabic a b j d, and alphabet is derived from the names of the two first letters in the Greek alphabet, alpha and beta. As Daniels used the word, an abugida is in contrast with a syllabary, where letters with shared consonants or vowels show no particular resemblance to one another, and also with an alphabet proper, where independent letters are used to denote both consonants and vowels. The term alphasyllabary was suggested for the Indic scripts in 1997 by William Bright, following South Asian linguistic usage, to convey the idea that "they share features of both alphabet and syllabary."