Synonyms

unable

American

[uhn-ey-buhl] / ʌnˈeɪ bəl /

adjective

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

He was unable to swim.

unable British

/ ʌnˈeɪbəl /

adjective

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

See incapable.

Etymology

Origin of unable

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Georgia, 16, is taking GCSEs and was also unable to get on with coursework due to the problems signing in online.

From BBC • Apr. 7, 2026

This means most Iranians are unable to reach international websites and social media, with only homegrown services such as for banking, shopping and ride hailing still accessible.

From Barron's • Apr. 7, 2026

Representatives for both the city and the Police Department said Monday that they were unable to comment on pending litigation.

From Los Angeles Times • Apr. 7, 2026

An October 2024 launch party with Will Smith and Alicia Keys proved premature, as rushed work left hotels riddled with construction problems and unable to open without hundreds of millions of dollars of fixes.

From The Wall Street Journal • Apr. 6, 2026

I paced away from Regan and then paced back, unable to stand still.

From "Glitch" by Laura Martin

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023