hibernation (n.) Look up hibernation at Dictionary.com
1660s, "action of passing the winter" (of plants, insect eggs, etc.), from Latin hibernationem (nominative hibernatio) "the action of passing the winter," noun of action from past participle stem of hibernare "to winter, pass the winter, occupy winter quarters;" related to hiems "winter," from PIE *gheim- "snow, winter" (cognates: Sanskrit heman "in winter," Hittite gimmanza, Greek kheima, Old Church Slavonic zima, Lithuanian žiema "winter"). Meaning "dormant condition of animals" is from 1789.