unable
Americanadjective
adjective
-
lacking the necessary power, ability, or authority (to do something); not able
-
archaic incompetent
Synonym Usage
See incapable.
Etymology
Origin of unable
Explanation
If you're unable to do something, you just can't do it. This isn't necessarily a bad thing! You may be unable to tell a lie, no matter how much you want to blame your brother for breaking that window. When we're unable, we're incapable. If you're unable to speak French, but you speak German fluently, you might choose to spend the summer in Berlin rather than Quebec City. And when your neighbor is unable to walk her dog during the day, you could volunteer to walk it after school. Being unable is either "lacking ability," or "lacking power."
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.
They were unable to save him, and he was declared dead shortly after, according to the LAFD.
From Los Angeles Times • Jun. 10, 2026
However, we have been unable to verify that organ removal took place.
From BBC • Jun. 9, 2026
So people currently in the program would see their funding cut off on June 30, 2027, and the program would be unable to sign up new enrollees as of that date.
From MarketWatch • Jun. 9, 2026
But they were unable to do so, while the head of Dassault Aviation continued to insist that the firm could go it alone on the project and was not in favour of it being "co-managed".
From Barron's • Jun. 8, 2026
"This is madness," cried Neel the potter, unable to keep silent any longer.
From "Rowan of Rin" by Emily Rodda
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
