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

Team members are always affected the most by old-fashioned work habits and inefficient operations— which cause the need for most transformation efforts. —Phil Gilbert, Fortune, 12 Nov. 2025

Instead, the judges say the court has become overcrowded and inefficient, with long wait times for services. —Ilana Arougheti, Kansas City Star, 12 Nov. 2025

Joel Quenneville’s immediate impact has been undeniable, while new assistants Jay Woodcroft and Ryan McGill have sparked improvement in what were terribly inefficient special teams last season. —Eric Stephens, New York Times, 11 Nov. 2025

The current solution — bulky, power-intensive external heating and cooling — is inefficient and only offers a limited operational range of -30°C to 45°C. —Mrigakshi Dixit, Interesting Engineering, 5 Nov. 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