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
Derived 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.
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
“The prior and ongoing vetting by other agencies and entities has been insufficient to determine whether the claims are fraudulent,” he stated.
From Los Angeles Times • Jun. 11, 2026
Supplements may be useful when dietary intake is insufficient or osteoporosis is present, but excessive intake should be avoided.
From Science Daily • Jun. 6, 2026
"It didn't limit student use of AI in any way -- so, completely insufficient, inadequate."
From Barron's • Jun. 5, 2026
The kilns in the neighbouring villages were kept busy firing the bricks, but their output was insufficient, and the carts had to go farther afield, returning dusty and brick-filled.
From "Nectar in a Sieve" by Kamala Markandaya
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.
