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

To address this, a lottery system for applicants was put in place, which critics say is manifestly inefficient. —Andrew R. Chow, Time, 23 Sep. 2025

But the reality is that data centers are inefficient, guzzling water and consuming huge amounts of electricity. —Senior Reporter, PC Magazine, 23 Sep. 2025

This behavior contributes to rolling traffic jams, an inefficient pattern compared to maintaining a steady pace, Guter pointed out. —Stuart Dyos, USA Today, 22 Sep. 2025

Without holistic profiling, teams miss how upstream bottlenecks, inefficient data serialization or chatty APIs cascade into latency and resource waste. —Expert Panel®, Forbes.com, 19 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