Vrddhi (वृद्धि, IAST: vṛddhi) is a Sanskrit word meaning "growth"[1] (from PIE *werdh `to grow'[2]). In Panini's grammar, it is also a technical term for a group of long vowels. In Indo-European linguistics, it has become a term for the lengthened grade of the ablaut vowel gradation peculiar to the Indo-European languages. A vrddhi-derivation is a word that is derived by such lengthening, a type of formation very common in Sanskrit, but also attested in other languages.
- ^ In Sanskrit, it's a -ti-nomen actionis formed from the verbal root vṛdh-/vardh- `to grow'.
- ^ *werdh `to grow' entry at Indo-European etymological database of The Tower of Babel project
