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

Leaky roofs, inefficient heating and deteriorating buildings — those are just a few of the improvements that need to be made within Lodi schools. — Carmela Karcher, CBS News, 29 Sep. 2026

Field agents endure inefficient routing and prolonged idle times between assignments, and passengers experience frustrating delays at gates or baggage claims. — Justin Newell, Forbes.com, 28 Sep. 2026

Many residents, community leaders and experts say that the current approach — which favors armed confrontations between police and the groups — is inefficient and often results in indiscriminate loss of life. — ABC News, 27 Sep. 2026

Every year, by design, the law forces thousands of inefficient old vehicles off the road as the cost of compliance rises and parts become harder to find. — Kyle Cheromcha, The Drive, 24 Sep. 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