# hibernation

/ˌhaɪbɝˈneɪʃən/ (US) · /hˌaɪbənˈeɪʃən/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/hibernation
Updated: 2026-05-11

## Definition

a long, deep sleep that some animals take during the winter to save energy. In computing, it is a mode where a computer saves its state and turns off to save power.

For teachers: a state of inactivity and metabolic depression in endotherms, characterized by low body temperature and slow breathing. In a computing context, refers to a power-management mode that saves the contents of RAM to disk before shutting down.

## Examples

- Bears enter hibernation to survive the cold winter months.
- The laptop enters hibernation automatically when the battery level drops below five percent to prevent data loss.
- While true hibernation involves profound physiological changes, some species only enter a lighter state of torpor, allowing them to wake quickly if the ambient temperature rises unexpectedly.

## Usage notes

- Uncountable in its biological sense; often used with the verb 'to enter' or 'to emerge from'.

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