risorius

noun

risorius

noun

UK /ɹɪˈsɔː.ɹi.əs/ · US /ɹɪˈsɔɹ.i.əs/

Etymology Borrowed from Late Latin rīsōrius (“ridiculous, laughing”), clipping of mūsculus rīsōrius (“laughing muscle”).

Anatomy, Medicine, Sciences A narrow band of facial muscle arising from the fascia over the masseter and inserting into the tissues at the corner of the mouth, which it draws laterally, as is used when smiling.

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.