"A flat, fan-shaped muscle that originates from the superior genial tubercle and inserts onto the undersurface of the tongue and onto the hyoglossal ligament, acting mainly to extend or protrude the tongue. Frequently attributive, especially in genioglossus muscle", Early 17th cent.; earliest use found in Helkiah Crooke (1576–1648), physician and anatomist. From post-classical Latin genioglossus from ancient Greek γένειον chin + γλῶσσα tongue, with alteration of the ending after classical Latin mūsculus muscle.[genioglossus etymology, genioglossus origin, 英语词源]