ret·ro·flex / ˈretrəˌfleks/ (also ret·ro·flexed) • adj. Anat. & Med. turned backward: a retroflex fibers. ∎  Phonet. pronounced with the tip of the tongue curled up toward the hard palate: the retroflex /r/.DERIVATIVES: ret·ro·flex·ion / ˌretrəˈflekshən/ n.

RETROFLEX. Sometimes retroflexed. A term in PHONETICS for sounds, especially /r/, made with the tip of the tongue curled back and raised towards the palate. These R-SOUNDS occur in such rhotic varieties of English as AmE (non-Southern), CanE, IndE, IrE, and the accents of south-west England, in which postvocalic /r/ coalesces with a following alveolar consonant in words like worse and hard. The process is known as retroflexion. In the languages of the Indian subcontinent, retroflex consonants such as /t/ and /d/ are common and occur in South Asian English.