IPA: /haɪˈbɜrnˌeɪtə/
KK: /haɪˈbɜrnˌeɪtər/
A creature or organism that goes into a state of deep sleep during certain seasons, usually to survive cold weather or lack of food.
Bears are well-known hibernators that sleep through the winter months.
Hibernator → It is formed from "hibernare" (meaning to spend the winter) and "-or" (meaning one who). The word refers to one who spends the winter, typically in a state of dormancy or inactivity.
Think of someone who 'spends the winter' ('hibernare') — that's why a hibernator is one who hibernates.