insufficient
Americanadjective
-
not sufficient; lacking in what is necessary or required.
an insufficient answer.
- Synonyms:
- deficient, scanty, inadequate
-
deficient in force, quality, or amount; inadequate.
insufficient protection.
adjective
Other Word Forms
Etymology
Origin of insufficient
First recorded in 1350–1400; Middle English, from Late Latin insufficient-, stem of insufficiēns; equivalent to in- 3 + sufficient
Explanation
If something is insufficient, it isn't enough. A high school diploma is very helpful for getting a job, but by itself, it's probably insufficient to land you a job as an astronaut. Something adequate is sufficient, and something inadequate is insufficient (in- meaning "not"). If you have $100 in the bank and you try to use a debit card for a $102 purchase, even though you’re close to having enough, your funds are insufficient to cover the sale. Anything that falls short of a required amount or expected measure is insufficient, whether it's the amount of air in a bike tire or the votes needed to win an election.
Vocabulary lists containing insufficient
Figurative Language in King's "I Have a Dream" Speech (1963)
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Martin Luther King Jr.'s "I Have a Dream" Speech (1963)
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Bridge to Terabithia
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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.
Even an intervention from Treasury Secretary Scott Bessent proved insufficient in bringing down bond yields.
From The Wall Street Journal ● Sep. 16, 2026
“In light of evolving societal norms, the Commissioner deems there is insufficient justification for the continued use of marital status in automobile insurance rating,” the filing stated.
From Los Angeles Times ● Sep. 16, 2026
At Friday's session, US deputy ambassador Jeffrey Bartos said the existing embargo was "outdated" and "insufficient to address the realities of the war today".
From Barron's ● Sep. 11, 2026
"We see some horrors," he says, adding that current checks on new homes before handover are insufficient.
From BBC ● Sep. 4, 2026
If the magistrate decided there was insufficient evidence, the defendants were discharged.
From "Long Walk to Freedom" by Nelson Mandela
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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.