Anushtubh in Chandas glossary

Source: Śodhganga: a concise history of Sanskrit Chandaḥ literature

Anuṣṭubh (अनुष्टुभ्) is one of the twenty-six varieties of Sanskrit metres (chandas) mentioned in the Chandaśāstra 1.15-19. There are 26 Vedic metres starting with 1 to 26 letters in each pāda. It is a common belief that the classical metres are developed from these 26 metres. Generally a metre has a specific name according to it’s number of syllables (akṣaraḥ). But sometimes the same stanza is called by the name of another metre from the point of view of the pādas.

Anuṣṭubh is one of the seven prominent metres mentioned by Piṅgala as being associated with the Devatā (deity): Soma, Svara (note): Gāndhāra, Colour: yellow and Gotra (family): Gautama.

According to Kṣemendra, the metre Anuṣṭubh should be used in books which reflect the Purāṇas, show the right path of duties and mainly aiming at imparting advice. A wise poet should use the metre Anuṣṭubh in the beginning (ārambha) of a Mahākāvya written in various sargas, the description of a quoted topic (kathāprasaṅga) and also in the context of a didactical (śamopadeśa) work.

Source: Knowledge Traditions & Practices of India: Language and Grammar (chandas)

Anuṣṭubh (अनुष्टुभ्) is the name of a metre used in Sanskrit prosody (chandas): one of the six vedāṅgas: disciplines developed in order to articulate and interpret sacred texts (such as the Ṛgveda).—Of the many metrical arrangements, anuṣṭubh is the most frequently employed metre in the classical Sanskrit literature and the epics Rāmāyaṇa and Mahābhārata have used this metre.