n. pl. hi·ber·nac·u·la (-lə)
1. A protective case, covering, or structure, such as a plant bud, in which an organism remains dormant for the winter.
2. The shelter of a hibernating animal.
[Latin hībernāculum, winter residence, from hībernāre, to winter, from hībernus, relating to winter; see ghei- in the Appendix of Indo-European roots.]
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