Dictionary.com
Thesaurus.com
Synonyms

inefficient

American  
[in-i-fish-uhnt] / ˌɪn ɪˈfɪʃ ənt /

adjective

  1. not efficient; unable to effect or achieve the desired result with reasonable economy of means.

  2. lacking in ability, incompetent.


inefficient British  
/ ˌɪnɪˈfɪʃənt /

adjective

  1. unable to perform a task or function to the best advantage; wasteful or incompetent

  2. unable to produce the desired result

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

See incapable.

Other Word Forms

  • inefficiency noun
  • inefficiently adverb

Etymology

Origin of inefficient

First recorded in 1740–50; in- 3 + efficient

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Instead banks are lending to inefficient state-owned enterprises and investment pools linked to local governments.

From The Wall Street Journal • Mar. 19, 2026

While this method produces very durable final products, it uses significant quantities of expensive raw materials and generates inefficient yields.

From Science Daily • Mar. 13, 2026

It was his most inefficient shooting performance with more than 11 shots of his career.

From Los Angeles Times • Mar. 11, 2026

What struck me most was the assumption beneath it all: that stopping to eat is not indulgent or inefficient, but necessary.

From Salon • Feb. 19, 2026

He became inefficient, less able to see and judge the objective world.

From "Black Boy" by Richard Wright