Vedic accent

The tone accent of Vedic Sanskrit, or Vedic accent for brevity, is traditionally divided by Sanskrit grammarians into three qualities, udātta "raised" (acute accent, high pitch), anudātta "not raised" (grave accent, low pitch) and svarita "sounded" (circumflex, falling pitch).

The accents
Udātta marks the place of the inherited PIE accent. In transliteration, therefore, udātta is usually marked with an acute accent, and anudātta and svarita are unmarked since their positions follow automatically from the position of udātta. For example, in the first pada of the Rigveda, the transliteration
 * "Agni I praise, the high priest."
 * "Agni I praise, the high priest."

means that the eight syllables have an intonation of
 * A-U-S-A-A-U-S-A (where A=anudātta, U=udātta, S=svarita),

or iconically,
 * _¯\__¯\_


 *  is a finite verb and thus has no udātta, but its first syllable is svarita because the previous syllable is udātta.
 * Vedic meter is independent of Vedic accent and exclusively determined by syllable weight, so that metrically, the pada reads as
 * -.--.-.x (viz., the second half-pada is iambic).

In some cases an accented syllable disappeared due to linguistic changes in oral transmission of the samhita before it was written down, so that a svarita may be next after an anudātta: this is a so-called "independent svarita". In such cases, the svarita syllable is marked in transcription with a grave accent.

For example in RV 1.10.8c,
 * U-S-U-S-A-A-A-U
 * ¯\¯\___¯
 * ¯\¯\___¯

became
 * U-S-S-A-A-A-U
 * ¯\\___¯
 * ¯\\___¯

Independent svarita is caused by sandhi of adjacent vowels. There are four variants of it:- Independent svarita occurs about 1300 times in the Rigveda, or in about 5% of padas.
 * ' (= "innate") (due to changes within a word, as in ' for , as in the example above (u becomes v before a vowel)
 * ' (= "caused by quickness") (u becoming v or i becoming y where two words meet, as in ' for ) (i becomes y before a vowel)
 * ' (= "coalescence") (vowel contraction where two words meet, as in ' for )
 * ' (= "close contact") (prodelision with avagraha where two words meet, as in ' for ).

Notation
In Roman alphabet transcription, udātta is marked with an acute accent, independent svarita is marked with a grave accent, and other syllables are not marked with accent.

In Devanagari editions of the Rigveda samhita:
 * Svarita is marked with a small upright stroke above a syllable.
 * Anudātta is marked with a horizontal line below the syllable, if it is next before an udātta or an independent svarita. If the first syllable in a pada is anudātta, that syllable and all following syllables which are anudātta are marked with the horizontal line, up to and not including the first syllable which is not an anudātta.
 * If an independent svarita syllable is next before an udātta syllable, instead of putting the anudātta mark and the svarita mark on the same syllable, a figure 1 (if the svarita vowel is short) or a figure 3 (if the svarita vowel is long) is written between, and that figure has the svarita mark and the anudātta mark.
 * Other syllables are unmarked.