define

American  

[dih-fahyn] / dɪˈfaɪn /

verb (used with object)

defined, defining

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

   They disagreed on how to define “liberal.”

2. to explain or identify the nature or essential qualities of; describe.

   to define judicial functions.

3. to fix or lay down clearly and definitely; specify distinctly.

   to define one's responsibilities.

   Synonyms:

   enumerate, detail, describe, name, state

4. to determine or fix the boundaries or extent of.

   to define property with stakes.

5. to make clear the outline or form of.

   The roof was boldly defined against the sky.

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verb (used without object)

defined, defining

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

define British  

/ dɪˈfaɪn /

verb

1. to state precisely the meaning of (words, terms, etc)

2. to describe the nature, properties, or essential qualities of

3. to determine the boundary or extent of

4. (often passive) to delineate the form or outline of

   the shape of the tree was clearly defined by the light behind it

5. to fix with precision; specify

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Other Word Forms

• definability
  noun
• definable
  adjective
• definably
  adverb
• definement
  noun
• definer
  noun
• misdefine
  verb (used with object)
• nondefinability
  noun
• nondefinable
  adjective
• nondefinably
  adverb
• nondefined
  adjective
• nondefiner
  noun
• predefine
  verb (used with object)
• redefine
  verb (used with object)
• self-defined
  adjective
• semidefined
  adjective
• undefinable
  adjective

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.

Example Sentences

Last week, I wrote about the overuse of the slang-suffix “-maxxing” in nutritional spaces, underscoring why the rhetoric we use to define how we nourish ourselves matters so greatly.

From Salon • May 17, 2026

Employing more than 8.5 million people, WPA built bridges, roads, public buildings, parks and airports, while supporting artists, writers and musicians whose work helped define American culture.

From The Wall Street Journal • May 14, 2026

"Jason spent eight seasons in a Nets uniform, helping define an era of our franchise and playing a vital role on our back-to-back Eastern Conference championship teams in 2002 and 2003," the team said.

From BBC • May 13, 2026

It is a key ingredient in many of the technologies researchers hope will define the future, including quantum computing, quantum communication, quantum teleportation, and quantum networks.

From Science Daily • May 13, 2026

In Eugene Maleska crossword terminology, he's braw and pulchritudinous, while Will Shortz, current puzzle editor for The New York Times, might define him as a "wower," the clue being "Turns heads, in a way."

From "Me Talk Pretty One Day" by David Sedaris

Related Words

• characterize
• construe
• decide
• delineate
• describe
• designate
• detail
• determine
• exemplify
• explain
• illustrate
• interpret
• prescribe
• represent
• specify
• spell out