unable

[uhn-ey-buhl]

adjective

1. lacking the necessary power, competence, etc., to accomplish some specified act.

   He was unable to swim.

unable

/ ʌnˈeɪbəl /

adjective

1. lacking the necessary power, ability, or authority (to do something); not able

2. archaic,  incompetent

Word History and Origins

Origin of unable¹

First recorded in 1350–1400; Middle English; un- ¹ + able

Synonym Study

See incapable.

Example Sentences

So why has Bihar been unable to enforce its ban more effectively?

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Calculators and computers didn’t render generations unable to do math, and modern-day versions are far more advanced than in 1980.

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Penelope had always preferred early bedtimes, but in Plinkst she often found herself unable to sleep.

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Indeed, there had only been one time during all Penelope’s student days in which she had been unable to complete an assignment, and the memory of it still made her itch.

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“Perhaps Lady Constance will not be the only surprise to tumble out of the Ashton family ‘tree,’” she thought, unable to resist a leafy pun of her own.

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Related Words

• helpless 
• impotent 
• inadequate 
• incapable 
• not able 
• powerless 
• sidelined www.thesaurus.com
• unfit 
• weak