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

The fact that the President is now signalling a messy retreat has nothing to do with insufficient lethality and everything to do with politics—in particular, the alarm in the global oil markets and the American public’s widespread opposition to the war. —Benjamin Wallace-Wells, New Yorker, 3 Apr. 2026

Eric Lampkin-Scarborough, 19, was arrested for insufficient bonds related to a felony weapon charge and a misdemeanor evading arrest charge. —Briauna Brown, CBS News, 1 Apr. 2026

Henning filed a motion to vacate in May 2024 on numerous grounds, including insufficient evidence and police and prosecutorial misconduct. —Rocco Parascandola, New York Daily News, 1 Apr. 2026

The case could render birth certificates alone insufficient citizenship proof. —Devin Dwyer, ABC News, 1 Apr. 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