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

Experts say the overall patchwork of federal and state funding for call centers remains insufficient to meet the true level of need. —Devi Shastri, Fortune, 24 Apr. 2026

Granted, there was a lot to criticize in my writing, which was suffering from all sorts of problems, from structural incoherence to insufficient character development to—yes—didactic heavy-handedness that broke the reader’s immersion. —Literary Hub, 23 Apr. 2026

During the trip, officials heard direct complaints from local leaders and fire victims about insurers being slow, restrictive and insufficient with their claim payouts. —Justine McDaniel, Los Angeles Times, 23 Apr. 2026

The California Department of Justice report found insufficient evidence to support criminally prosecuting Silva. —Sierra Van Der Brug, Oc Register, 23 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