English Lexicon

Unstable

/ʌnˈsteɪ.bəl/
adjectiveCEFR B2 (Upper)Top #2150 frequency
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Comprehensive Definitions & Senses

2 senses
As adjective
  1. 1

    Prone to change, failing to hold a steady position, or likely to give way.

    "The injured climber stood on an unstable rock ledge."
  2. 2

    Experiencing frequent and unpredictable emotional swings or psychological distress.

    "His unstable mood made it difficult to predict how he would react."

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Antonyms & Contrasting Words (1)

Linguistic Origin & Historical Etymology

Derived from the Middle English 'unstable', combining the native Germanic negative prefix 'un-' (meaning 'not') with the Old French 'estable', which traces back to the Latin 'stabilis' meaning firm or steadfast. Over centuries, the term has evolved from describing physical structures lacking secure foundations to encompassing emotional volatility and political unpredictability.

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