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.
Meanwhile, 12% of Americans said insufficient child care options played a role in their decision to have fewer children than desired.
From MarketWatch • Jun. 16, 2026
Estimates were calculated for every 1km2 of terrestrial land, excluding ice caps and regions where data were insufficient for reliable predictions.
From Science Daily • Jun. 15, 2026
Defense Secretary John Healey resigned this past week in protest of what he saw as insufficient military funding proposed by Prime Minister Keir Starmer.
From The Wall Street Journal • Jun. 14, 2026
“Allegations are insufficient on their own to demonstrate that statements were in fact made with malice,” the judge wrote.
From Los Angeles Times • Jun. 12, 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.
