insufficient

adjective

in·​suf·​fi·​cient ˌin(t)-sə-ˈfi-shənt 

: not sufficient : inadequate

insufficient funds

especially : lacking adequate power, capacity, or competence

insufficient bandwidth

insufficiently adverb

Synonyms of insufficient

• lacking
• inadequate
• scarce
• low

Examples of insufficient in a Sentence

The case was thrown out because of insufficient evidence.

there's been an insufficient number of volunteers for the job, so I'll have to select someone

Recent Examples on the Web

Now, as ever, there may be some who hold McCartney’s cherubic good will against him, as a badge of insufficient seriousness. —Chris Willman, Variety, 23 May 2026

If there is insufficient rain, water regularly. —Nadia Hassani, The Spruce, 23 May 2026

This approach reflects an understanding that policy reform alone is insufficient. —Walter Pavlo, Forbes.com, 22 May 2026

To achieve these ends, electoral politics is essential but insufficient. —Chris Murphy, The Atlantic, 20 May 2026

Word History

Etymology

Middle English, from Anglo-French, from Late Latin insufficient-, insufficiens, from Latin in- + sufficient-, sufficiens sufficient

First Known Use

14th century, in the meaning defined above

Rhymes for insufficient

• beneficent
• coefficient
• inefficient
• deficient
• efficient
• omniscient
• proficient
• sufficient

Kids Definition

insufficient

adjective

in·​suf·​fi·​cient ˌin(t)-sə-ˈfish-ənt 

: not sufficient : inadequate

insufficiently adverb