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.
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
"There was also, at times, a lack of proper planning for the qualifiers and insufficient preparation for matches. That is why it took such a long time."
From BBC • Jun. 2, 2026
Author Andrew Lownie says there is still insufficient transparency in the UK about information relating to Mountbatten-Windsor and he's called for a parliamentary inquiry into his time as trade envoy.
From BBC • May 30, 2026
From herself to Jane—from Jane to Bingley, her thoughts were in a line which soon brought to her recollection that Mr. Darcy’s explanation there had appeared very insufficient, and she read it again.
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.
