Abjad

An abjad (/ˈæbdʒæd/ ^ⓘ or abgad) is a writing system in which only consonants are represented by letter signs, leaving the vowels to be inferred by the reader (unless represented otherwise, such as by diacritics). This contrasts with alphabets that provide graphemes for both consonants and vowels. The term was introduced in 1990 by Peter T. Daniels. Other terms for the same concept include partial phonemic script, segmentally linear defective phonographic script, consonantary, consonant writing, and consonantal alphabet.

Impure abjads represent vowels with either optional diacritics, a limited number of distinct vowel glyphs, or both.

The name abjad is based on the Arabic alphabet's first four letters in their original alphabetical order — corresponding to ʾa, b, j, and d  —  which reflects the alphabetical order ʾaleph, bet, gimel, dalet in other consonantal Semitic scripts such as Phoenician, Hebrew, and other Semitic proto-alphabets classified within the family of scripts used to write West Semitic languages.

According to the formulations of Peter T. Daniels, abjads differ from alphabets in that only consonants, not vowels, are represented among the basic graphemes. Abjads differ from abugidas, another category defined by Daniels, in that in abjads, the vowel sound is implied by phonology, and where vowel marks exist for the system, such as niqqud for Hebrew and ḥarakāt for Arabic, their use is optional and not the dominant (or literate) form. Abugidas mark all vowels (other than the "inherent" vowel) with a diacritic, a minor attachment to the letter, a standalone glyph, or (in Canadian Aboriginal syllabics) by rotation of the letter. Some abugidas use a special symbol to suppress the inherent vowel so that the consonant alone can be properly represented. In a syllabary, a grapheme denotes a complete syllable, that is, either a lone vowel sound or a combination of a vowel sound with one or more consonant sounds.

The contrast of abjad versus alphabet has been rejected by other scholars because abjad is also used as a term for the Arabic numeral system. Also, it may be taken as suggesting that consonantal alphabets, in contrast to e.g. the Greek alphabet, were not yet true alphabets. Florian Coulmas, a critic of Daniels and of the abjad terminology, argues that this terminology can confuse alphabets with "transcription systems", and that there is no reason to relegate the Hebrew, Aramaic or Phoenician alphabets to second-class status as an "incomplete alphabet". However, Daniels's terminology has found acceptance in the linguistic community.

The Proto-Sinaitic script represents the earliest-known trace of alphabetic writing. This script is generally considered to have been developed around the Sinai Peninsula during the Middle Bronze Age by speakers of an ancient West Semitic language who repurposed pictographic elements of local Egyptian hieroglyphs in order to construct a new script that represented the consonants of their own language using acrophony. The Proto-Sinaitic script is thought to represent, or at least indicate the existence of, an early ancestor of the many later Semitic consonantal scripts which continued to develop over time into more abstract, less visually representational forms, including the Phoenician abjad.

The Phoenician abjad was a radical simplification of phonetic writing. Unlike other scripts, such as Mesopotamian cuneiform (logographic and syllabic) and Egyptian hieroglyphs (logographic and consonantal), the Phoenician abjad consisted of only a few dozen symbols. Presumably, the relative simplicity of the Phoenician abjad made this script easy to learn, allowed it to gain widespread usage, and influenced how readily it was adopted or adapted into the development of other scripts by non-Phoenicians who encountered seafaring Phoenician merchants and their script which they brought with them as they traded throughout the ancient Mediterranean world during the first millennium BCE.

During these exchanges, the Phoenician script gave rise to a number of new writing systems, including the widely used Aramaic abjad and the Greek alphabet. The Greek alphabet was later developed into several alphabets, including Etruscan, Coptic, Cyrillic, and Latin (via Etruscan), while Aramaic became the ancestor of many abjads and abugidas of Asia, particularly in and around India, Southeast Asia, and Oceania.