inefficient

adjective

in·​ef·​fi·​cient ˌi-nə-ˈfi-shənt 

: not efficient: such as

a

: wasteful of time or energy

inefficient operating procedures

b

: incapable, incompetent

an inefficient worker

c

: not producing the effect intended or desired

used inefficient measures

inefficient noun

inefficiently adverb

Synonyms of inefficient

• unsuccessful
• ineffective
• counterproductive

Examples of inefficient in a Sentence

The delivery system was very inefficient.

an inefficient use of fuel

Recent Examples on the Web

In a fair sporting world, clubs with inefficient recruitment operations would be overtaken by smarter efforts, like those showcased at Brighton. — Chris Weatherspoon, New York Times, 12 Aug. 2026

On the other hand, detailed reviews of individual high-cost claims frequently reveal inefficient areas in an employer’s health plan. — Bruce Roffe, Forbes.com, 12 Aug. 2026

Canada’s crypto laws are already burdensome enough, but they are also layered on top of a fragmented and inefficient system of securities regulation. — Karia Samaroo, Fortune, 7 Aug. 2026

Earlier research had shown that unclonable encryption was possible, but existing approaches were either inefficient or needed certain assumptions to be secure. — Peter Hall, Scientific American, 31 July 2026

Word History

First Known Use

1750, in the meaning defined above

Rhymes for inefficient

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

Kids Definition

inefficient

adjective

in·​ef·​fi·​cient ˌin-ə-ˈfish-ənt 

1

: not producing the effect expected or desired

inefficient regulations

2

: wasteful of time or energy

inefficient procedures

especially : accomplishing little relative to the time spent or effort expended

an inefficient worker

inefficiently adverb