How Vowels Shift When Sanskrit Becomes Prakrit

Prakrit grammar and phonology
A friendly first look at what happens to Sanskrit vowels as they cross into Prakrit — the shortenings, the simplifications, and the little rules that keep the language flowing.

Table of Contents

    Series

    Post 1 of 5 in A Beginner's Tour of Prakrit Sound Change — how Sanskrit becomes Prakrit, drawn from Hemacandra's Siddhahemaśabdānuśāsana, Adhyāya VIII, Pādas 1–2.

    If you know a little Sanskrit and you open a Prakrit text for the first time, the words look almost familiar — as if someone had taken your favourite Sanskrit vocabulary and gently softened the corners. That softening is not random. Hemacandra, writing in the twelfth century, catalogued every one of these shifts in his grammar, the Siddhahema. This post is a short tour of what he found for vowels.

    We will not learn everything. The goal is only to give you a feel for the landscape, so that when you meet a Prakrit word in the wild you can say, "Ah — I see where that came from."

    Examples in:

    A note on the trailing “a”. In Devanāgarī every consonant sign carries a built-in a — क is ka, so the cluster त्य is written tya and its Prakrit result च्च is written cca. In a change such as त्य → च्च (tya → cca) or ट → ड (ṭa → ḍa), only the consonants actually change; the a is there just so the letters can be pronounced.

    The vowels Prakrit does not have

    Sanskrit has a rich vowel inventory. Prakrit trims it down. Three sets of Sanskrit vowels essentially disappear:

    • The vocalic liquids ऋ, ॠ, ऌ, ॡṛ, ṝ, ḷ, ḹ — the little r-vowels and l-vowels in words like कृतkṛta and मृगmṛga.
    • The diphthongs ai and au — usually. Some authorities keep them; most collapse them into simpler vowels.

    That leaves Prakrit with eight working vowels: अ, आ, इ, ई, उ, ऊ, ए, ओa, ā, i, ī, u, ū, e, o. Every Sanskrit vowel that isn't in this list has to become one that is. That single fact drives a huge amount of what follows.

    What happens to ṛ

    Sanskrit is the most common of the vocalic liquids, and Prakrit's default response is simple: it becomes short a.

    SanskritPrakritMeaning
    कृतkṛtaकयkayadone
    घृतghṛtaघयghayaghee
    मृगmṛgaमअmaadeer
    वृषभvṛṣabhaवसहvasahabull

    But has other lives too. In a smaller set of words it becomes i (as in कृपाkṛpāकिवाkivā, "pity"), and in another set it becomes u (as in ऋतुṛtuउउuu, "season"). When stands alone at the start of a word without any consonant attached, it becomes रिri — so ऋद्धिṛddhi "prosperity" appears as रिद्धिriddhi.

    Which of these outcomes you get depends on the word. There is a general default (a) and a handful of lexical pockets that take i, u, or रिri instead. When you learn Prakrit vocabulary, you learn which pocket a given Sanskrit word belongs to.

    What happens to the diphthongs

    The two Sanskrit diphthongs ai and au simplify at the start of a word:

    • ai becomes e
    • au becomes o
    SanskritPrakritMeaning
    वैद्यvaidyaवेज्जvejjaphysician
    शैलśailaसेलselamountain
    कौमुदीkaumudīकोमुईkomuīmoonlight
    यौवनyauvanaजोव्वणjovvaṇayouth

    There is a small exception. A group of words — दैत्यdaitya, भैरवbhairava, दैन्यdainya and a few others — keep the diphthong but spell it out as अइ (two syllables). So दैत्यdaitya "demon" appears as दइच्चdaïcca. If you see a Prakrit word with अइ or अउ, that's often what has happened.

    Long vowels shorten before a cluster

    Here is a rule that catches people off guard because it applies quietly, right in the middle of a word. Whenever a long vowel would sit directly before a consonant cluster in Prakrit, that vowel shortens.

    SanskritPrakritMeaning
    आम्रāmraअम्बambamango
    ताम्रtāmraतम्बtambacopper
    आस्यāsyaअस्सassamouth

    Notice what happens with आम्रāmra ― the ā shortens to a, and separately the cluster म्रmr becomes म्बmb. Two changes are stacking on top of each other. This is very typical of Prakrit — several rules touch the same word, and the final form is the product of all of them.

    Compensatory lengthening — a shortening rule that lengthens

    Sometimes a consonant drops out and the vowel next to it "absorbs" the lost sound by growing longer. This happens when y, r, v or a sibilant is elided in a cluster with a sibilant.

    SanskritPrakritMeaning
    पश्यतिpaśyatiपासइpāsaïhe sees
    अश्वaśvaआसāsahorse
    विश्रामviśrāmaवीसामvīsāmarest

    Here पश्यतिpaśyati loses the y, but the preceding a stretches into ā to compensate. The word feels balanced again. This is one of the most important rules to know because it produces so many familiar-looking Prakrit words with long vowels where you might have expected short ones.

    Compounds are flexible with length

    Inside a compound, vowels can shorten or lengthen freely. Hemacandra explicitly says this variation is optional. So the same underlying compound might show up two different ways in two different texts:

    SanskritPrakrit variantsMeaning
    वधूमुखvadhū-mukhaवहुमुहvahu-muha or वहूमुहvahū-muhabride's face
    नदीस्रोतस्nadī-srotasनइसोत्तnaï-sotta or नईसोत्तnaī-sottariver's current

    Neither form is wrong. This is the vikalpa principle — Hemacandra's way of saying "in practice, both are found." A translator or a learner has to accept that Prakrit is a bit more relaxed than Sanskrit about these small choices.

    A quick note on hiatus

    Sanskrit hates two vowels sitting next to each other, and its sandhi rules exist to smooth them out. Prakrit is the opposite — it is perfectly content with hiatus. When two vowels meet inside a Prakrit word, they usually just sit there, unmerged.

    पादःpādaḥ "foot" in Sanskrit becomes पाओpāo in Prakrit, with two vowels in a row. In Sanskrit that would trigger sandhi; in Prakrit it is the norm. This gives Prakrit its characteristic open, flowing sound.

    What to take away

    The vowel changes from Sanskrit to Prakrit are less about strict transformation and more about simplification and flow. The alphabet shrinks. Difficult vowels like find easier substitutes. Long vowels pull back when they meet clusters. Consonants can drop out and let the vowels sing. And where Sanskrit insists on merging vowels together, Prakrit leaves them side by side.

    In the next post we will turn to consonants — first the single, non-conjunct ones, where the language performs its most famous trick: making sounds vanish altogether.