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

Additionally, in a typical year, 17 million gallons of gas are spilled due to the inefficient manner the fuel is conveyed. —Chris Hildreth, The Orlando Sentinel, 26 Mar. 2026

With the help of Ware’s positive minutes, the Heat survived an inefficient shooting night from Adebayo. —Anthony Chiang, Miami Herald, 26 Mar. 2026

Several people posted on Facebook that a road diet would be inefficient and potentially make the road more dangerous. —Don Stacom, Hartford Courant, 25 Mar. 2026

Dean took aim at both the firings and the subsequent rehiring push, calling the cycle inefficient and costly. —Rena Rowe, The Washington Examiner, 25 Mar. 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