Abugida

An abugida (/ˌɑːbuːˈɡiːdə, ˌæb-/ ^ⓘ; from Geʽez: አቡጊዳ, 'äbugīda)—sometimes also called an alphasyllabary, neosyllabary, or pseudo-alphabet—is a segmental writing system in which consonant–vowel sequences are written as units; each unit is based on a consonant letter, and vowel notation is secondary, like a diacritical mark. 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 a single symbol denotes the combination of a consonant and a vowel.

Related concepts were introduced independently in 1948 by James Germain Février (using the term néosyllabisme) and David Diringer (using the term semisyllabary), and in 1959 by Fred Householder (introducing the term pseudo-alphabet). The Ethiopic term "abugida" was chosen as a designation for the concept in 1990 by Peter T. Daniels. Faber suggested "segmentally coded syllabically linear phonographic script"; William O. Bright used the term alphasyllabary; and Gnanadesikan and Rimzhim, Katz, & Fowler suggested aksara or āksharik.

Abugidas include the extensive Brahmic family of scripts of Tibet and South and Southeast Asia; Semitic Ethiopic scripts; and Canadian Aboriginal syllabics. As in syllabaries, the writing system's units may consist of representations of both syllables and consonants. For scripts of the Brahmic family, the term akshara is used for the units.

In several languages of Ethiopia and Eritrea, abugida traditionally meant letters of the Ethiopic or Geʽez script in which many of these languages are written. The Geʽez script is one of several segmental writing systems; others include Indic/Brahmic scripts and Canadian Aboriginal Syllabics. The word abugida derives from the letters 'ä, bu, gi, and da, in much the same way that abecedary derives from the Latin letters a be ce de, abjad derives from the Arabic a b j d, and alphabet derives from the two first letters in the Greek alphabet, alpha and beta. Abugida as a term in linguistics was proposed by Peter T. Daniels in his 1990 typology of writing systems.

As Daniels used the word, an abugida contrasts with a syllabary, where letters with shared consonant or vowel sounds have no particular resemblance. Furthermore, an abugida contrasts with an alphabet proper, where independent letters denote consonants and vowels. The term alphasyllabary was suggested for the Indic scripts in 1997 by William O. Bright, following South Asian linguistic usage, to convey that "they share features of both alphabet and syllabary."

The formal definitions given by Daniels and Bright for abugida and alphasyllabary differ; some writing systems are abugidas but not alphasyllabaries, and some are alphasyllabaries but not abugidas. An abugida is defined as "a type of writing system whose basic characters denote consonants followed by a particular vowel, and in which diacritics denote other vowels". (This "particular vowel" is called the inherent or implicit vowel, as opposed to the explicit vowels marked by the diacritics.)

An alphasyllabary is defined as "a type of writing system in which the vowels are denoted by subsidiary symbols, not all of which occur in a linear order (with relation to the consonant symbols) that is congruent with their temporal order in speech". Bright did not require that an alphabet explicitly represent all vowels. ʼPhags-pa is an example of an abugida because it has an inherent vowel, but it is not an alphasyllabary because its vowels are written in linear order. Modern Lao is an example of an alphasyllabary that is not an abugida, for there is no inherent vowel and its vowels are always written explicitly and not in accordance to their temporal order in speech, meaning that a vowel can be written before, below, or above a consonant letter, while the syllable is still pronounced in the order of a consonant-vowel combination (CV).

The fundamental principles of an abugida apply to words made up of consonant-vowel (CV) syllables. The syllables are written as letters in a straight line, where each syllable is either a letter that represents the sound of a consonant and its inherent vowel or a letter modified to indicate the vowel. Letters can be modified either by means of diacritics or by changes in the form of the letter itself. If all modifications are by diacritics and all diacritics follow the direction of the writing of the letters, the abugida is not an alphasyllabary. But most languages have words that are more complicated than a sequence of CV syllables, even ignoring tone.