- hibernation
- 1664, from L. hibernationem (nom. hibernatio "the action of passing the winter," from hibernare "to winter," from hiems "winter," from PIE *gheim- "snow, winter" (cf. Skt. heman "in winter," Hittite gimmanza, Gk. kheima, O.C.S. zima, Lith. ziema "winter"). Hibernate is first attested 1802.