hibernaculum

American  

[hahy-ber-nak-yuh-luhm] / ˌhaɪ bərˈnæk yə ləm /

Also hibernacle

noun

hibernacula plural

1. a protective case or covering, especially for winter, as of an animal or a plant bud.

2. winter quarters, as of a hibernating animal.

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hibernaculum British  

/ ˌhaɪbəˈnækjʊləm, ˈhaɪbəˌnækəl /

noun

1. the winter quarters of a hibernating animal

2. the protective case or covering of a plant bud or animal

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hibernaculum Scientific  

/ hī′-bər-năk′yə-ləm /

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.

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Other Word Forms

Inflected Forms

noun

• hibernacula
  plural

Etymology

Origin of hibernaculum

First recorded in 1690–1700; from Latin hībernāculum “winter residence,” equivalent to hībernā(re) “to spend the winter” + -culum suffix denoting place

Explanation

If a cave is handy, a bear might choose it as its hibernaculum, a place to spend the winter while it's in a state of winter dormancy. A groundhog's hibernaculum is an elaborate underground burrow in which it spends the winter in a deep sleep. The word hibernaculum is borrowed from Latin, where it means "winter home." It's related to the English word hibernate, which is what some animals do to survive the harsh, winter months: They go into a deep, prolonged state of inactivity. A hibernaculum can be as simple as a hard, protective covering on an insect (or plant), or a pile of leaves to snuggle down in. While hibernaculum is a specific term in zoology and biology, it may be used figuratively to describe a person's winter retreat.

Example Sentences

Those offspring hibernate over winter as larvae - caterpillars - in a communal silken web called a hibernaculum.

From BBC • Nov. 30, 2025

Eric Weaver, the monument’s branch chief of natural resources, says Junction Cave has the largest known hibernaculum in the monument for Townsend’s big-eared bats.

From Washington Times • Oct. 12, 2019

Construction of the winter cave, or hibernaculum, cost about $300,000.

From Washington Post • Oct. 29, 2012

It is the winter home, or hibernaculum, to 270,000 gray bats, listed as endangered partly because the entire species hibernates in only nine caves, three of those in Tennessee.

From New York Times • Sep. 24, 2012

You have not come out your hibernaculum too early or too late; the time is ripe, and, if you do not keep pace with the rest, why, the fault is not in the season.

From A Year in the Fields by Burroughs, John