Consonantal writing, annotated
An abjad writes the consonants and leaves the vowels to the reader. This reference explains how the system works: which signs are obligatory, how small marks above and below the line supply the vowels, and how the old letter order doubled as a number system.
| Writing system | Letters |
|---|---|
| Phoenician | 22 |
| Aramaic | 22 |
| Hebrew | 22 |
| Arabic | 28 |
| Syriac | 22 |
| Ugaritic | 30 |
A writing system whose letters stand for consonants, with vowels left to the reader or shown by optional marks.
The word itself is an acronym of the old Arabic letter order — alif, ba, jim, dal — the same way 'alphabet' spells out alpha and beta. As a technical term it is recent: the linguist Peter T. Daniels proposed it in 1990 to give consonantal scripts a name of their own.
In an abjad the consonantal skeleton is the text. A sequence like k-t-b in Arabic carries the root idea of writing, and the vowels that turn it into 'he wrote', 'it was written' or 'books' come from grammar, not from the letters. Three consonant letters — alif, waw and ya — can double as long-vowel carriers, a device known by the Latin term matres lectionis.
The type is old. The earliest consonantal signs appear in Proto-Sinaitic inscriptions of roughly 1850 BCE, and the 22-letter Phoenician script that followed became the parent of Aramaic, Hebrew, Syriac and Arabic — every major abjad in use or attested today.
Dates before the common era are approximate and follow the conventional scholarly ranges.
Fluency, morphology and context do the work that vowel letters do in an alphabet.
Semitic languages build words on consonantal roots, usually of three letters, slotted into fixed vowel patterns. Because the patterns are few and the vocabulary is organised around roots, a fluent reader can predict most vowels from the shape of the word and its place in the sentence.
Where a word remains genuinely ambiguous — a name, a rare form, a homograph — writers can point it. Fully vocalised text is the norm in scripture, in children's primers, in learners' materials and in dictionaries; newspapers, novels and street signs are printed without marks.
The system trades letters for reader effort, and it has been stable for well over a thousand years, because the consonantal skeleton changes far more slowly than pronunciation.
Small signs above and below the letters show which vowel follows — and they are the only part of the system that is optional.
Arabic uses a set of strokes called harakat: a small stroke above the letter (fatha) for a, a stroke below (kasra) for i, and a tiny comma-like damma above for u. A sukun marks a letter with no vowel at all, and a shadda marks a doubled consonant.
Hebrew developed its pointing later, in the Tiberian school of the Masoretes between the seventh and ninth centuries CE: a grid of dots and dashes placed mostly under the letters, the niqqud, which fixed the traditional pronunciation of the biblical text.
Both systems sit outside the letter line, so they can be added or omitted without touching the consonants. That separability is the defining feature of the abjad: the vowel marks are a commentary layer, not part of the letter inventory.
The reading list points to standard reference works on Semitic writing systems, the history of the alphabet and the vocalisation of Hebrew and Arabic.