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.
The wide-ranging proposals say reactive action would be insufficient, and online marketplaces would need to "act with due care to prevent, identify and remove dangerous products being sold via their platforms".
From BBC • Apr. 15, 2026
Sukhdeep Singh, who owns Merced County-based Cali Brothers Truck Lines, said standard surcharge policies are insufficient when there are wild swings in fuel prices.
From Los Angeles Times • Apr. 9, 2026
Fare increases are likely insufficient to offset higher fuel costs for Air China, China Southern Airlines and China Eastern Airlines, the analyst adds.
From The Wall Street Journal • Apr. 8, 2026
On Monday, he said a temporary ceasefire proposal being circulated was insufficient.
From Barron's • Apr. 7, 2026
It was going to Halifax and the cold turn the weather had taken and his insufficient clothing made him desire a trip to the tropic Sugar Isles above all else.
From "Johnny Tremain" by Esther Hoskins Forbes
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.
