Devanagari Ai ऐ

Ai is the twelfth letter of the varnamala and the second of the combination vowels. In the grammarians' scheme it stands one degree beyond e: where e is the first strengthening of i, ai is the second, produced by the process the tradition calls vrddhi. Like all four sandhyakshara it is always long and always makes its syllable heavy in metre, and like them it has no short counterpart in the series. Its vowel sign is a pair of slanted strokes above the headline, distinguished from the single stroke of e only by the doubling, which is one of several places in Devanagari where a longer or stronger sound is written as the shorter sign with something added. The letter is common in derived vocabulary precisely because the second strengthening grade is used to form a large class of derivatives, including patronymics, adjectives of relation and abstract nouns, so a word beginning with ai is very often a formation built on a root whose own vowel is i or e.

Recognising that is part of reading Sanskrit efficiently, since the strengthened vowel signals the derivation before the rest of the word is parsed. The independent letter is used where a word opens with the vowel or where the vowel follows another across a join, and the rules by which it arises are stated in the same body of grammar that produces e.

The letter also arises through the euphonic combination that Sanskrit applies at every word boundary. Long a followed by i or by e yields ai, so a written or recited passage carries the letter at joins where the separated words had no such vowel at all, and a reader has to undo the combination to recover them. Sanskrit is unusual in applying these changes in its writing rather than leaving them to the speaker, with the result that a manuscript line can run as a single unbroken sequence of sounds in which the word divisions have been chemically altered. That is one of the harder features of the language for a beginner and one of the reasons Sanskrit editions vary in how much they separate words for the reader. In recitation the length of ai is held, since the classical metres count syllables as light or heavy and every combination vowel makes its syllable heavy.

The oral traditions that carry the Vedic and epic corpora train these quantities deliberately, and the recitation styles that repeat and permute the words of a text exist in part to keep them from drifting. In the Tantric reading of the alphabet as a garland of matrika the letter belongs with the other vowels to the class the traditions treat as preceding the consonants, and it is one of the fifty counted. Further attributions belong to the schools that make them.