Synonyms

define

American

[dih-fahyn] / dɪˈfaɪn /

verb (used with object)

to state or set forth the meaning of (a word, phrase, etc.).

They disagreed on how to define “liberal.”
to explain or identify the nature or essential qualities of; describe.

to define judicial functions.
to fix or lay down clearly and definitely; specify distinctly.

to define one's responsibilities.

Synonyms:

enumerate, detail, describe, name, state
to determine or fix the boundaries or extent of.

to define property with stakes.
to make clear the outline or form of.

The roof was boldly defined against the sky.

verb (used without object)

to set forth the meaning of a word, phrase, etc.; construct a definition.

define British

/ dɪˈfaɪn /

verb

to state precisely the meaning of (words, terms, etc)
to describe the nature, properties, or essential qualities of
to determine the boundary or extent of
(often passive) to delineate the form or outline of

the shape of the tree was clearly defined by the light behind it
to fix with precision; specify

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Derived Forms

Inflected Forms

Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of define

First recorded in 1325–75; Middle English def(f)inen, from Anglo-French, Old French definer “to put an end to,” from Latin dēfīnīre ”to limit, define,“ equivalent to dē- “from, away from, out of” + fīnīre “to end”; see origin at de-, finish

Explanation

If you can't define a word, turn to the dictionary. That's always the best way to learn the definition. Likewise, anything you can describe completely is something you can define. The early French and Latin roots of the verb mean something closer to "to limit" or "to create a boundary," but this is really what we do when we define something: we limit its meaning to something specific. So when you're thinking about the word define, remember that you're looking to create a boundary of meaning around it, whether you're specifying the meaning of a word or a larger concept. To define a word such as astronomy is to define both the word and the realm of science that it's concerned with.

Keep Reading on Vocabulary.com

Vocabulary lists containing define

The Language of Standardized Tests, List 1

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Jim Burke's Academic Vocabulary List

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The ACT: The Language of the Test, List 1

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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.

See Examples For:

define defines defined defining

The companies that used to define an index, going public early in their growth, now opt to wait.

From MarketWatch ● Aug. 15, 2026

Their conversation explores characters who hide their true nature behind carefully constructed personas, the role of technology in enabling obsession and revenge, and the social rituals that define contemporary London.

From Slate ● Aug. 15, 2026

"Points to consider include how do you define a pet - does the policy just cover cats and dogs or would hamsters, rabbits, goldfish, horses, snakes, or other animals be included?"

From BBC ● Aug. 15, 2026

To stop this practice, the report suggested measures including artificial-intelligence tools at the border to scan cargo and documents, and tightening standards that define a product’s country of origin.

From The Wall Street Journal ● Aug. 14, 2026

Write and define adjectives denoting abounding in, having the quality of, from the following nouns:—

From New Word-Analysis by William Swinton

“Offering a generous 20-foot-wide footprint and spanning 5,000 square feet, this six-bedroom, six-bath residence defines timeless urban sophistication,” the listing crowed.

From MarketWatch ● Aug. 6, 2026

The U.S. became what the United Nations defines as an “aging society,” where at least 7% of the population is over 65, in the early 1940s.

From The Wall Street Journal ● Jul. 26, 2026

The get-rich ethos that defines our time may be only rivaled by our perilously tantalizing obsession with vengeance.

From Salon ● Jul. 19, 2026

The law defines "take" to mean "harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct."

From Barron's ● Jul. 14, 2026

It’s the way we deal with what Fate hands us that defines who we are.

From "A Tangle of Knots" by Lisa Graff

Over his first two seasons in the majors, Paul Skenes’s career was defined by making the impossible look mundane.

From The Wall Street Journal ● Aug. 14, 2026

Their goal was to understand how people first learn the value of different options in clearly defined situations and which options they later favor when those choices are presented in new combinations.

From Science Daily ● Aug. 13, 2026

Much of his rule was defined by the civil war.

From BBC ● Aug. 11, 2026

Take a look at the accompanying chart, which is based on the trailing five-year relative strength of midcap stocks, defined as the 40% of stocks in the middle of the market-cap distribution of U.S. stocks.

From MarketWatch ● Aug. 11, 2026

Often, such music calls for notes that are a little more separate or defined than legato, but still nowhere as short as staccato.

From "Understanding Basic Music Theory" by Catherine Schmidt-Jones and Russel Jones

The results suggest that one of the proton's defining quantum properties may not reside solely in its three valence quarks.

From Science Daily ● Aug. 16, 2026

Something new to listen to: Six years ago, indie rocker Phoebe Bridgers’ last solo album became one of the defining records of the decade.

From Slate ● Aug. 14, 2026

Of course, when the dancers of the Los Angeles Ballet dress for rehearsal, they’re not concerned with defining a trendy aesthetic.

From Los Angeles Times ● Aug. 11, 2026

His red card against Paris St-Germain in the 2024 Champions League quarter-finals became one of the defining moments of his Barcelona career, with his dismissal helping turn the tie in PSG's favour.

From BBC ● Aug. 10, 2026

They activate and silence genes, thereby defining the embryo’s axis from head to tail.

From "The Gene" by Siddhartha Mukherjee

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023