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Definitions

inefficient

[in-i-fish-uhnt] / ˌɪn ɪˈfɪʃ ənt /
ADJECTIVE
not working well; wasteful
Synonyms
STRONGEST
disorganized faulty feeble incompetent ineffective ineffectual inept sloppy weak
WEAK
can't hack it careless extravagant half-baked improficient improvident incapable inefficacious inexpert not cut out for prodigal shooting blanks slack slipshod slovenly unfit unprepared unqualified unskilled unskillful untrained
Antonyms
STRONGEST
able capable competent dexterous effective fit neat skillful sound strong tidy
WEAK
efficient expert useful

Frequently Asked Questions

What is another word for inefficient?
Inefficient is a way of saying that something (or someone) works in a way that wastes effort or energy—in other words, that it’s not efficient. This isn’t always easy to boil down to one word. A process that’s considered inefficient could be described as wasteful, meaning that it could get the same (or an even better) result with less effort or resources. Processes that are efficient are sometimes described as economical—meaning they maximize results with minimum resources or effort. In this way, something that’s inefficient could be described as uneconomical. You could indicate that a process is inefficient by saying that it involves too many steps. You could imply that a machine is inefficient by saying that it doesn’t run as smoothly as it should. Old appliances are called inefficient when they use way more energy to perform the same functions as more efficient ones. You could imply that a person is inefficient in the way they’re completing a task or doing an activity by saying that they’re doing unnecessary work or exerting more effort than they need to. Sometimes, instead of saying that something is inefficient, you could say that it suffers from inefficiency.
What is an example of something that’s inefficient?
All kinds of things can be described as inefficient, including:
  • Machines, such as a gas-guzzling car or an old washing machine that uses up a lot of energy. Rube Goldberg machines are intentionally inefficient and overly complicated.
  • People, such as a worker who completes tasks in roundabout ways or a runner who exerts unnecessary energy during each stride.
  • Processes, such as a project that uses more of the budget than it needs to or involves more employees than is necessary.
  • Institutions and organizations. People often accuse the government of being inefficient. An inefficient business is one that uses more resources than are necessary to operate.
How do you use inefficient in a sentence?
Inefficient is commonly used. It can describe people, machines, systems, and institutions, among other things. Here are some examples of inefficient in a sentence: 
  • Without my monitor and mouse, I can still get work done, but I’m really inefficient—it takes me an hour to do what usually takes 10 minutes!
  • Some people say that the government is too inefficient and should be run like a business. 
  • My car is so inefficient—it only gets 8 miles to the gallon.

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.

He would work to end inefficient programs and opaque financing, his campaign website states.

From Los Angeles Times • May 1, 2026

CenterPoint wrote that keeping the plant open “will require substantial investment to support an inefficient and increasingly unreliable asset, rather than advancing affordable and reliable service for customers in southwestern Indiana.”

From Barron's • Apr. 20, 2026

Deutsche Lufthansa LHA -1.23%decrease; red down pointing triangle will gradually cut capacity and ground inefficient aircraft to tackle extra costs derived from the Iran war and the impact of strikes.

From The Wall Street Journal • Apr. 16, 2026

This complex acts to selectively suppress mRNAs that contain non-optimal codons, effectively reducing the production of inefficient genetic messages.

From Science Daily • Apr. 9, 2026

Then he said, “Yeah. Sure. Do you know how inefficient trees are, next to an air factory?”

From "Feed" by M.T. Anderson

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