Sanskrit prosody


 * See Vedic meter for meter in Vedic Sanskrit.

Versification in Classical Sanskrit poetry is of three kinds.
 * 1) Syllabic verse (akṣaravṛtta): meters depend on the number of syllables in a verse, with relative freedom in the distribution of light and heavy syllables.  This style is derived from older Vedic forms, and found in the great epics, the Mahabharata and the Ramayana.
 * 2) Syllabo-quantitative verse (varnavṛtta): meters depend on syllable count, but the light-heavy patterns are fixed.
 * 3) Quantitative verse (mātrāvṛtta): meters depend on duration, where each verse-line has a fixed number of morae, usually grouped in sets of four.

Standard traditional works on meter are Pingala's Chandaḥśāstra and Kedāra's Vṛttaratnākara. The most exhaustive compilations, such as the modern ones by Patwardhan and Velankar contain over 600 metres. This is a substantially larger repertoire than in any other metrical tradition.

Light and heavy syllables
In most of Sanskrit poetry the primary determinant of a meter is the number of syllables in a unit of verse, called the pāda ("foot", not to be confused with the "foot" of Western prosody). Meters of the same length are distinguished by the pattern of laghu ("light") and guru ("heavy") syllables in the pāda.

The rules distinguishing laghu and guru syllables are the same as are specified in Vedic texts such as the Pratisakhyas. They can be summarized as:
 * 1) A syllable is laghu only if its vowel is hrasva ("short") and followed by at most one consonant before another vowel is encountered.
 * 2) A syllable with an anusvara ('ṃ') or a visarga ('ḥ') is always guru.
 * 3) All other syllables are guru, either because the vowel is dīrgha ("long"), or because the hrasva vowel is followed by a consonant cluster.
 * 4) The hrasva vowels are the short monophthongs: 'a', 'i', 'u', 'ṛ' and 'ḷ'
 * 5) All other vowels are dīrgha: 'ā', 'ī', 'ū', 'ṝ', 'e', 'ai', 'o' and 'au'.  (Note that, morphologically, the last four vowels are actually the diphthongs 'ai', 'āi', 'au' and 'āu', as the rules of sandhi in Sanskrit make clear.  So, while an original 'ai', for example, had been shortened to an 'e' sound in practice, it was still to be treated as long metrically.  The original short 'e' and short 'o' sounds had already been assimilated into short 'a' in the Proto-Indo-Iranian period of the language. )

For measurement by morae, laghu syllables count as one unit, and guru syllables as two units. The standard unit of grouping, analogous to the "foot" of Western prosody, is four morae (four laghus, two gurus, or a guru and two laghus).

Gaṇa
Gaṇa (Sanskrit, "group") is the technical term for the pattern of light and heavy syllables in a sequence of three. It is used in treatises on Sanskrit prosody to describe meters, according to a method first propounded in Pingala's chandaḥśāstra.

Pingala's method described any meter as a sequence of gaṇas, or triplets of syllables, plus the excess, if any, as single units. There being eight possible patterns of light and heavy syllables in a sequence of three, this scheme called for ten descriptive elements in all. With each of these ten, Pingala associated a letter, allowing the meter to be described compactly as an acronym. His encoding scheme was as follows


 * The units:
 * l: a "light" syllable (L), called laghu
 * g: a "heavy" syllable (H), called guru


 * The gaṇas:
 * m : H-H-H, called ma-gaṇa
 * y : L-H-H, called ya-gaṇa
 * r : H-L-H, called ra-gaṇa
 * s : L-L-H, called sa-gaṇa
 * t : H-H-L, called ta-gaṇa
 * j : L-H-L, called ja-gaṇa
 * bh: H-L-L, called bha-gaṇa
 * n : L-L-L, called na-gaṇa

Pingala's order of the gaṇas, viz. m-y-r-s-t-j-bh-n, corresponds to a standard enumeration in binary, when the three syllables in each gaṇa are read right-to-left with H=0 and L=1.

An example
The definition of the meter Vasantatilakā given by Kedāra in his Vṛttaratnākara is


 * uktā vasantatilakā tabhajā jagau gaḥ

which can be decoded as


 * tabhajā jagau gaḥ = t bh j j g g = H-H-L-H-L-L-L-H-L-L-H-L-H-H

Note that Kedāra's definition is itself an example of the meter.

A mnemonic
The word yamātārājabhānasalagāḥ (or yamātārājabhānasalagaṃ), invented by medieval commentators, is a mnemonic for Pingala's gaṇas, using the vowels "a" and "ā" for light and heavy syllables respectively with the letters of his scheme. In the form without a grammatical ending, yamātārājabhānasalagā is self-descriptive, where the structure of each gaṇa is shown by its own syllable and the two following it:


 * ya-gaṇa: ya-mā-tā = L-H-H
 * ma-gaṇa: mā-tā-rā = H-H-H
 * ta-gaṇa: tā-rā-ja = H-H-L
 * ra-gaṇa: rā-ja-bhā = H-L-H
 * ja-gaṇa: ja-bhā-na = L-H-L
 * bha-gaṇa: bhā-na-sa = H-L-L
 * na-gaṇa: na-sa-la = L-L-L
 * sa-gaṇa: sa-la-gā = L-L-H

The mnemonic also encodes the light "la" and heavy "gā" unit syllables of the full scheme.

The truncated version obtained by dropping the last two syllables, viz. yamātārājabhānasa, can be read cyclically (i.e., wrapping around to the front). It is an example of a De Bruijn sequence.

Comparison
The gaṇas are not the same as prosodic feet in Greek or Latin poetry, although there is a correspondence (m-y-r-s-t-j-bh-n = molossus, bacchius, cretic, anapest, antibacchius, amphibrach, dactyl, choreus). The difference is that the gaṇas are analytic devices only, and do not indicate internal structure as "feet" do. For instance, a phalaecian verse consisting of a spondee, a dactyl and three trochees would be analysed as m-s-j-g-l (i.e. a molossus, an anapest, an amphibrach and a trochee); similarly a sapphic verse as r-t-j-g-l (cretic, antibacchius, amphibrach and trochee).

Akṣarachanda
Most of classical Sanskrit poetry is of the varṇavṛtta type, also called akṣarachanda. Stanzas are quatrains of four pādas (verses), with the metrical structure of each pāda completely specified. In some cases, pairs of pādas may be scanned together as the hemistichs of a couplet. It is then normal for the pādas comprising a pair to have different structures, to complement each other aesthetically. Otherwise the four pādas of a stanza will have the same structure.

Epic poetry
While the Mahabharata has various types of versification, an overwhelming proportion of the stanzas (all but about 0.2%) are akṣaravṛtta (free syllabic). Within this majority, 95% are shlokas of the anustubh type and the rest are tristubhs.

Moraic poetry

 * mātrāchanda:
 * 1) puṣpitāgrā
 * 2) aparavaktra
 * 3) vaitālīya
 * 4) mātrāsamaka
 * gaṇachanda:
 * 1) āryā
 * 2) āryāgīti
 * 3) upagīti