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

inefficient noun

inefficiently adverb

Synonyms

• 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

Technology has removed many of the barriers that used to make solopreneurship inefficient. —Matteo Pittaluga, Forbes.com, 9 Sep. 2025

Chad Wackerman, a drummer and teacher, believes this change in technique —favoring the biceps over the wrist to create a louder sound — is to blame for an inefficient playing style. —Devon Ivie, Vulture, 3 Sep. 2025

Neural networks are surprisingly inefficient learners and contain a lot of redundant information, says Mugel, which leaves a lot of room for optimization. —IEEE Spectrum, 3 Sep. 2025

She’s brought in outside consultants to help the finance office fix its inefficient accounting systems, drawing praise from state officials. —Rory Linnane, jsonline.com, 3 Sep. 2025

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