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)
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Martin Luther King Jr.'s "I Have a Dream" Speech (1963)
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Bridge to Terabithia
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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
The DOE is also expected to provide uranium for reactor fuel where “commercial sources are insufficient or unavailable.”
From Barron's • Apr. 14, 2026
Ships transiting the strait were also excluded where there was insufficient data that they followed the Larak route.
From The Wall Street Journal • Apr. 11, 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
But even more than that, I think, the man understood that words were insufficient.
From "The Things They Carried" by Tim O'Brien
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.
