Definition of efficient
- the efficient action of heat in changing water to steam
- an efficient worker
that manual lawn mower is not a very efficient tool for doing a huge yard
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'efficient.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
These three words cover some overlapping territory.
Efficient most often describes what is capable of producing desired results without wasting materials, time, or energy. While the word can be applied to both people and things, it is far more commonly applied to things, such as machines, systems, processes, and organizations. The focus of the word is on how little is wasted or lost while the desired results are produced.
Effective typically describes things—such as policies, treatments, arguments, and techniques—that do what they are intended to do. People can also be described as effective when they accomplish what they set out to accomplish, but the word is far more often applied to things.
Proficient typically describes people, and it often is followed by the preposition at. If you are proficient at something, you are very good at it. You are, in fact, so good at doing it that you are unusually efficient when you do it. One can also be proficient in something, such as a language.
First Known Use: 14th centurySee Words from the same year
: capable of producing desired results without wasting materials, time, or energy
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