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definition

noun

def·​i·​ni·​tion ˌde-fə-ˈni-shən 

1

a

: a statement of the meaning of a word or word group or a sign or symbol

dictionary definitions

b

: a statement expressing the essential nature of something

c

: a product of defining

2

: the action or process of stating the meaning of a word or word group

3

a

: the action or the power of describing, explaining, or making definite and clear

the definition of a telescope

her comic genius is beyond definition

b(1)

: clarity of visual presentation : distinctness of outline or detail

improve the definition of an image

(2)

: clarity especially of musical sound in reproduction

c

: sharp demarcation of outlines or limits

a jacket with distinct waist definition

4

: a clear or perfect example of a person or thing

the very definition of a gentleman

5

: an act of determining

specifically : the formal proclamation of a Roman Catholic dogma

definitional

ˌde-fə-ˈni-sh(ə-)nəl 

adjective

Synonyms of definition

• description
• portrait
• depiction
• portrayal

Examples of definition in a Sentence

For the last eight years or so, I've been watching the evolution of bikes made for women. At the beginning of that time, there were a small number of women's bikes available, most offered with low-end, sometimes no-name, spec, as if by definition all women riders were beginners. —Christine Bucher, Bicycling, March 2008

Not only is Ellen Byrne a chocolatier, but she takes the definition of artisan to a higher level. —Amy Johansson, Chocolatier, February/March 2006

One kind of poverty is that of the imagination—the inability to envision a future truly different from the present. Jasmine had long judged people based on whether or not they gave her food and clothing, but, as she watched Carolyn and Gus and other families, she found herself mulling different gauges of worth. She'd been working lately on a definition of love. —Katherine Boo, New Yorker, 28 Nov. 2005

Ideology thus provides definition of both systemic reality and values: it provides a set of preconceptions of what is and of what ought to be. —Warren J. Samuels, Modern Economic Thought, (1977) 1993

What is the legal definition of a corporation?

A week of fishing is my definition of a vacation.

a monitor with good definition and vibrant colors

Recent Examples on the Web

Living and working across Southeast Asia reinforced early on in his career that there is no universal definition of exclusivity in luxury and what creates meaning for one guest may be entirely different for another. — Jeetendr Sehdev, Forbes.com, 1 Aug. 2026

In Cairo, two Egyptian sources said Hamas had agreed to several contentious points, including the handover of weapons, but had requested changes regarding the definition of the infrastructure to be dismantled, adding more talks were underway. — Reuters, NBC news, 31 July 2026

In my mind, the definition stuck until, as with so many things in the NBA, LeBron changed the game. — Dan Woike, New York Times, 31 July 2026

There are some very fine definitions of where conch will like to spend their time. — Sarah Perkel, USA Today, 31 July 2026

Word History

Etymology

Middle English diffinicioun, borrowed from Anglo-French diffiniciun, definiciun, borrowed from Latin dēfīnītiōn-, dēfīnītiō "fixing of a boundary, precise description," from dēfīnīre "to mark the limits of, determine, define" + -tiōn-, -tiō, suffix of verbal action

First Known Use

14th century, in the meaning defined at sense 5

Phrases Containing definition

• by definition
• high-definition
• self-definition

Rhymes for definition

• abolition
• acquisition
• admonition
• ammunition
• apparition
• apposition
• coalition
• competition
• composition
• deglutition
• demolition
• deposition

Kids Definition

definition

noun

def·​i·​ni·​tion ˌdef-ə-ˈnish-ən 

1

: an act of determining or settling the limits

2

a

: a statement of the meaning of a word or word group or a sign or symbol

b

: the action or process of defining

3

a

: the action or the power of making definite and clear

b

: clarity, distinctness

definitional

-ˈnish-nəl 

-ən-ᵊl

adjective

Medical Definition

definition

noun

def·​i·​ni·​tion ˌdef-ə-ˈnish-ən 

: the action or the power of making definite and clear

the definition of a microscope lens