History of Sanskrit (Phonology - Vowels)

Phonology

Further information: Śikṣā

Classical Sanskrit distinguishes about 36 phonemes. There is, however, some allophony and the writing systems used for Sanskrit generally indicate this, thus distinguishing 48 sounds.

The sounds are traditionally listed in the order vowels (Ach), diphthongs (Hal), anusvara and visarga, plosives (Sparśa) and nasals (starting in the back of the mouth and moving forward), and finally the liquids and fricatives, written in IAST as follows:

a ā i ī u ū ṛ ṝ ḷ ḹ ; e ai o au

ṃ ḥ

k kh g gh ṅ; c ch j jh ñ; ṭ ṭh ḍ ḍh ṇ; t th d dh n; p ph b bh m

y r l v; ś ṣ s h

An alternate traditional ordering is that of the Shiva Sutra of Pāṇini.

Vowels

The vowels of Classical Sanskrit written in Devanagari, as a syllable-initial letter and as a diacritic mark on the consonant प् (/p/), pronunciation transcribed in IPA, IAST, and approximate equivalent in English:

Letter	प्	IPA	IAST	English equivalent (GA unless stated otherwise)
अ	प	/ɐ/ or /ə/	a	short near-open central vowel or schwa: u in bunny
आ	पा	/ɑː/	ā	long open back unrounded vowel: a in father (RP)
इ	पि	/i/	i	short close front unrounded vowel: e in england
ई	पी	/iː/	ī	long close front unrounded vowel: ee in feet
उ	पु	/u/	u	short close back rounded vowel: oo in foot
ऊ	पू	/uː/	ū	long close back rounded vowel: oo in cool
ऋ	पृ	/r̩/	ṛ	syllabic alveolar trill: closest to er in butter in rhotic accents
ॠ	पॄ	/r̩ː/	ṝ	syllabic alveolar trill: closest to ir in bird in rhotic accents
ऌ	पॢ	/l̩/	ḷ	syllabic dental lateral approximant: le in turtle
ॡ	पॣ	/l̩ː/	ḹ	syllabic dental lateral approximant: longer le
ए	पे	/eː/	e	long close-mid front unrounded vowel: a in bane (some speakers)
ऐ	पै	/əi/	ai	a long diphthong: i in ice, i in kite (US, Canadian, and Scottish English)
ओ	पो	/oː/	o	long close-mid back rounded vowel: o in bone (Scottish English)
औ	पौ	/əu/	au	a long diphthong: ou in house (Canadian English)

The long vowels are pronounced twice as long as their short counterparts. Also, there exists a third, extra-long length for most vowels, called pluti, which is used in various cases, but particularly in the vocative. The pluti is not accepted by all grammarians.

The vowels /e/ and /o/ continue as allophonic variants of Proto-Indo-Iranian /ai/, /au/ and are categorised as diphthongs by Sanskrit grammarians even though they are realised phonetically as simple long vowels.

Additional points:

• There are some additional signs traditionally listed in tables of the Devanagari script:
  • The diacritic ं called anusvāra, (IAST: ṃ). It is used both to indicate the nasalisation of the vowel in the syllable [◌̃] and to represent the sound of a syllabic /n/ or /m/; e.g. पं /pəŋ/.
  • The diacritic ः called visarga, represents /əh/ (IAST: ḥ); e.g. पः /pəh/.
  • The diacritic ँ called chandrabindu, not traditionally included in Devanagari charts for Sanskrit, is used interchangeably with the anusvāra to indicate nasalisation of the vowel, primarily in Vedic notation; e.g. पँ /pə̃/.
• If a lone consonant needs to be written without any following vowel, it is given a halanta/virāma diacritic below (प्).
• The vowel /aː/ in Sanskrit is realised as being more central and less back than the closest English approximation, which is /ɑː/. But the grammarians have classified it as a back vowel.^[41]
• The ancient Sanskrit grammarians classified the vowel system as velars, retroflexes, palatals and plosives rather than as back, central and front vowels. Hence ए and ओ are classified respectively as palato-velar (a+i) and labio-velar (a+u) vowels respectively. But the grammarians have classified them as diphthongs and in prosody, each is given two mātrās. This does not necessarily mean that they are proper diphthongs, but neither excludes the possibility that they could have been proper diphthongs at a very ancient stage. These vowels are pronounced as long /eː/ and /oː/ respectively by learned Sanskrit Brahmans and priests of today. Other than the "four" diphthongs, Sanskrit usually disallows any other diphthong—vowels in succession, where they occur, are converted to semivowels according to sandhi rules.