definition

American  

[def-uh-nish-uhn] / ˌdɛf əˈnɪʃ ən /

noun

definitions plural

1. the act of defining, or of making something definite, distinct, or clear.

   We need a better definition of her responsibilities.

2. the formal statement of the meaning or significance of a word, phrase, idiom, etc., as found in dictionaries. An online dictionary resource, such as Dictionary.com, can give users direct, immediate access to the definitions of a term, allowing them to compare definitions from various dictionaries and stay up to date with an ever-expanding vocabulary.

3. the condition of being definite, distinct, or clearly outlined.

   His biceps have great muscle definition.

4. Optics. sharpness of the image formed by an optical system.

5. Radio and Television. the accuracy of sound or picture reproduction.

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definition British  

/ ˌdɛfɪˈnɪʃən /

noun

1. a formal and concise statement of the meaning of a word, phrase, etc

2. the act of defining a word, phrase, etc

3. specification of the essential properties of something, or of the criteria which uniquely identify it

4. the act of making clear or definite

5. the state or condition of being clearly defined or definite

6. a measure of the clarity of an optical, photographic, or television image as characterized by its sharpness and contrast

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Other Word Forms

Derived Forms

• predefinition
  noun
• redefinition
  noun
• self-definition
  noun
• subdefinition
  noun
• definitional
  adjective
• definitionally
  adverb

Inflected Forms

Nouns

• definitions
  plural

Etymology

Origin of definition

First recorded in 1350–1400; Middle English diffinicioun, from Old French diffinition, from Latin dēfīnītiōn- (stem of dēfīnītiō ), equivalent to dēfīnīt(us) ( see definite) + -iōn- noun suffix ( see -ion)

Explanation

A good definition explains concisely what something means. Dictionaries include definitions, even for the word definition! A definition precisely explains the fundamental state or meaning of something, often given formally as by lexicographers writing a dictionary or legislators writing laws. It can also refer to a sharply detailed image or concept — like how clear the picture is on a high-definition TV or how cut a Calvin Klein model's abs are.

Example Sentences

See Examples For:

definition definitions

Some studies treat biphasic sleep as one long sleep plus a brief nap; others count only two equal periods; there is no agreed definition.

From BBC ● Jul. 19, 2026

Governing AI risks globally “is by definition going to need the U.S. and China both involved,” said Webster, who focuses on Chinese tech policy.

From The Wall Street Journal ● Jul. 17, 2026

“There are certain people,” says curator Zoé Whitley, “who redefined what was a very narrow definition of American art, and Betye is absolutely one of them.”

From Los Angeles Times ● Jul. 15, 2026

Actually, nobody on Wall Street has a good definition of risk, which is why they hide behind Greek letters and jargon: Sharp ratios, Sortino ratios, Treynor ratios and so on.

From MarketWatch ● Jul. 14, 2026

“Although,” said Irian, “their definition of treasure varies. There’s people who’ve hunted the carbuncles for months and dug up a rat’s tail and three fish heads.”

From "Impossible Creatures" by Katherine Rundell

Many people are afraid to pursue a path that runs counter to conventional definitions of success.

From MarketWatch ● Jul. 20, 2026

The states’ case hinges on whether a judge will accept the market definitions outlined in their lawsuit, Garcia and other analysts said.

From Los Angeles Times ● Jul. 15, 2026

Talk about two very different definitions of sausages.

From The Wall Street Journal ● Jun. 25, 2026

But in practice, the movement’s definitions of good and how to maximize it are at times controversial.

From Slate ● Jun. 2, 2026

The award-winning poster included ten tips for running a successful lemonade stand, a profit-and-loss statement, business definitions, and a chart that tracked franchise profits.

From "The Lemonade War" by Jacqueline Davies

Related Words

• answer
• explanation
• interpretation
• rationale
• solution
• translation