English · Word Candidate

unstable

/ʌnˈsteɪ.bəl/

Proposed by a contributor, not yet supported by evidence.

Also seen as: unstables · unstabling · unstabled

Sense 1

Meaning · English

Not stable.

Adjective

Examples

unstable foundation

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).

Sense 2

Meaning · English

Having a strong tendency to change.

Adjective

Examples

The dawn of the oil age was fairly recent. Although the stuff was used to waterproof boats in the Middle East 6,000 years ago, extracting it in earnest began only in 1859 after an oil strike in Pennsylvania.[…]It was used to make kerosene, the main fuel for artificial lighting after overfishing led

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).

Sense 3

Meaning · English

To release (an animal) from a stable.

Verb

Examples

When the last tune of music floated from the fleet, he unstabled his quarter horse and headed for the coastal road leading west and north on his circuit.

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).

Common questions

What does “unstable” mean?

Not stable.

Is “unstable” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.