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

Much has been debated about when or whether this will happen, but neuroscientists like me and my colleagues can’t even truly agree on a definition of what consciousness is.

From The Wall Street Journal ● Sep. 30, 2026

Young people who end up playing in the NFL are, by definition, by far the fittest and strongest in their schools and colleges.

From MarketWatch ● Sep. 30, 2026

He said he cannot believe, nearly ten years after the fire, that government officials, the fire safety industry and developers are still wrestling with the definition of what is safe.

From BBC ● Sep. 30, 2026

Its definition of "allurement" includes employment, free education at a religious institution, a promise of marriage, a "better lifestyle" and "divine healing".

From BBC ● Sep. 29, 2026

“You can barely detect the definition in my cheekbones.”

From "The Last Last-Day-of-Summer" by Lamar Giles

But critics say its broad definitions, severe penalties and scrutiny of even voluntary conversions risk drawing the state and the police into one of the most private decisions a person can make.

From BBC ● Sep. 29, 2026

That meant LGBTQ+ and single people who historically had been shut out by definitions of infertility as a failure to conceive after six to 12 months of unprotected heterosexual intercourse.

From Los Angeles Times ● Sep. 27, 2026

The authority of the ICJ was built on the precise legal definitions established by figures like Raphael Lemkin, who coined “genocide,” and Sir Hersch Lauterpacht, who helped shaped the concept of “crimes against humanity.”

From The Wall Street Journal ● Sep. 22, 2026

The lack of shared definitions across a fast-moving industry is also stalling AI safety efforts.

From MarketWatch ● Sep. 19, 2026

It was empowering to help dismantle the definitions of beauty that too often erased women of color and almost never included hijabi women.

From "Proud" by Ibtihaj Muhammad

Related Words

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