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.
They can apply to ban marches outright where these powers are deemed insufficient to prevent "serious public disorder", but this requires the approval of the home secretary and is not regularly used.
From BBC • May 2, 2026
The Salt Lake County district attorney’s office and the Draper City prosecutor both declined to file charges against Paul in April, citing insufficient evidence to prove allegations beyond a reasonable doubt.
From Los Angeles Times • Apr. 30, 2026
The firm estimates demand losses of about 1.6 million barrels a day—significant, but insufficient to offset the current supply shortfall.
From The Wall Street Journal • Apr. 30, 2026
Despite global shortages, U.S. natural gas producers face oversupply and insufficient pipeline capacity, leading to negative prices in Texas.
From Barron's • Apr. 24, 2026
As for Olmsted, Burnham was struck by the slightness of his frame, which seemed structurally insufficient to support so massive a skull.
From "The Devil in the White City" by Erik Larson
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.
