B2adjective2K

Unstable

UK //ˌʌnˈsteɪbəl//US //ʌnˈsteɪbəl//

Definition

Not firm, steady, or secure; prone to change or failure.

In simple words: Not steady or secure, often likely to change or fail.

Examples

  • The weather in spring can be quite unstable.
  • Investing in unstable markets can lead to significant losses.
  • Their relationship felt unstable after the argument.
  • The bridge was declared unstable after the earthquake.
  • Unstable conditions in the economy raise concerns for investors.

Usage notes

Used in both everyday and technical contexts. Avoid in conversations where positive connotations are expected.

Grammar pattern

unstable + noun

Memory hint

Think of unstable as 'un-steady', like a wobbly table.

Collocations

  • unstable condition
  • unstable situation
  • unstable environment
  • unstable economy
  • unstable relationship

Synonyms

  • precarious
  • volatile
  • shaky
  • fickle
  • insecure

Antonyms

  • stable
  • secure
  • steady

Common mistakes

  • Confused with 'stable' — remember that unstable means not stable.
  • Using it to describe people directly without context—better for situations or conditions.