Chandas — The Science of Vedic and Sanskrit Metre
Chandas ('metre, that which covers/protects'; from chad = 'to cover, to please') is the third of the six Vedāṅgas — the systematic study of the metrical patterns that structure Vedic and classical Sanskrit poetry. The name itself is significant: metre 'covers' (protects) the Vedic mantras, ensuring their structural integrity.
The Vedic literature is organized in metres, each with a specific number of syllables per verse and specific patterns of heavy (guru) and light (laghu) syllables. The primary Vedic metres include:
- Gāyatrī (24 syllables: 3 × 8) — the most sacred of all metres, used in the Gāyatrī mantra (Om bhūr bhuvaḥ svaḥ... from Ṛgveda 3.62.10), recited daily at sandhyāvandana (twilight worship)
- Triṣṭubh (44 syllables: 4 × 11) — the most common metre of the Ṛgveda, used in many hymns to Indra and Viṣṇu
- Jagatī (48 syllables: 4 × 12) — used extensively in the Ṛgveda, especially in hymns to Varuna
- Anuṣṭubh (32 syllables: 4 × 8) — the dominant metre of Sanskrit classical literature (the Rāmāyaṇa, Mahābhārata, and Bhagavad-gītā are primarily in anuṣṭubh)
In ritual (yāga), knowing the chandas of a mantra is one of the six required pieces of knowledge before its use: ṛṣi (seer), chandas (metre), devatā (deity), bīja (seed syllable), śakti (power), and kīlaka (pin). The priest must announce these before the mantra is recited.
For the Divya Prabandham, the Tamil equivalents — kali (kaliṭṭuṟai, kalinilai), aṭi (foot-count), and aṭi-meter — are the corresponding metrical science, and the Āzhvārs' mastery of Tamil prosody is itself considered a divine gift.