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.
He also said he was shocked by the poor construction of the buildings, with plastic foam having been used as mortar filler between cement slabs and insufficient reinforcing steel.
From The Wall Street Journal • Jul. 9, 2026
The company’s AI strategy has long been criticized, as investors saw insufficient return on the billions of dollars that Meta poured into hiring top researchers for Meta Superintelligence Labs and toward building data centers.
From MarketWatch • Jul. 9, 2026
A review of case reports from nine people who self-administered coffee enemas also concluded that there’s insufficient evidence to prove that the practice is helpful, and that it could be harmful, to the colon.
From Los Angeles Times • Jul. 8, 2026
But while Yang provided similar assistance to authorities, his offences were so "grave" that his assistance "was insufficient to warrant a more lenient punishment", the Changzhou court said.
From BBC • Jul. 7, 2026
If I have wounded your sister’s feelings, it was unknowingly done and though the motives which governed me may to you very naturally appear insufficient, I have not yet learnt to condemn them.
From "Pride and Prejudice" by Jane Austen
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.
