/huy'beuhr nak"yeuh leuhm/ , n. , pl. hibernacula /-leuh/ .
1. a protective case or covering, esp. for winter, as of an animal or a plant bud.
2. winter quarters, as of a hibernating animal.
Also, hibernacle /huy"beuhr nak'euhl/ .
[ 1690-1700; hibernaculum winter residence, equiv. to hiberna ( re ) (see HIBERNATE) + -culum -CULE 2 ]