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
- insufficiently adverb
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 tried to market the fund in 2024—speculation was that he was trying to raise $25 billion—but he pulled the deal because of insufficient demand.
From Barron's • Apr. 27, 2026
This led to delays in escalation, a failure to call an ambulance when needed, and insufficient planning for emergencies.
From BBC • Apr. 23, 2026
During the trip, officials heard direct complaints from local leaders and fire victims about insurers being slow, restrictive and insufficient with their claim payouts.
From Los Angeles Times • Apr. 22, 2026
The DOE is also expected to provide uranium for reactor fuel where “commercial sources are insufficient or unavailable.”
From Barron's • Apr. 14, 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.
