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 petition is separate from an appeal Troconis has filed alleging there was insufficient evidence to convict her and that several errors were made during the trial. —Justin Muszynski, Hartford Courant, 10 Jan. 2026

Democrats largely reject this idea as insufficient for covering the high costs of health care. —Alexandra Kukulka, Chicago Tribune, 9 Jan. 2026

The lawsuit also alleged that Tesla has provided insufficient warnings or training for occupants to have a safe exit after a crash. —Andrea Guzmán, Austin American Statesman, 8 Jan. 2026

The complaint goes on to state that immediately after the erroneous payment was recognized, the governor’s office attempted to reverse the direct deposits, but could not do so due to Cook having insufficient funds in his accounts. —Tim Dunn, Boston Herald, 8 Jan. 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