definitive

American  

[dih-fin-i-tiv] / dɪˈfɪn ɪ tɪv /

adjective

1. most reliable or complete, as of a text, author, criticism, study, or the like.

   the definitive biography of Andrew Jackson.

2. serving to define, fix, or specify definitely.

   to clarify with a definitive statement.

3. having its fixed and final form; providing a solution or final answer; satisfying all criteria.

   the definitive treatment for an infection; a definitive answer to a dilemma.

   Synonyms:

   supreme, ultimate, absolute, complete

4. Biology. providing the environment in which a fully developed parasite is able to reproduce, as is provided by a definitive host.

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noun

1. a defining or limiting word, as an article, a demonstrative, or the like.

2. Philately. a stamp that is a regular issue and is usually on sale for an extended period of time.

definitive British  

/ dɪˈfɪnɪtɪv /

adjective

1. serving to decide or settle finally; conclusive

2. most reliable, complete, or authoritative

   the definitive reading of a text

3. serving to define or outline

4. zoology fully developed; complete

   the definitive form of a parasite

5. 1. (of postage stamps) permanently on sale

   2. (as noun) a definitive postage stamp

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noun

1. grammar a word indicating specificity of reference, such as the definite article or a demonstrative adjective or pronoun

Other Word Forms

• definitiveness
  noun
• nondefinitiveness
  noun
• undefinitiveness
  noun
• nondefinitive
  adjective
• undefinitive
  adjective
• definitively
  adverb

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Etymology

Origin of definitive

First recorded in 1350–1400; Middle English, from Old French, from Latin dēfīnītīvus, equivalent to dēfīnīt(us) ( see definite) + -īvus adjective suffix ( see -ive)

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Explanation

A definitive answer is a final one. A definitive decision by a court of law is one that will not be changed. A definitive translation is one everyone turns to as correct. Definitive means authoritative, conclusive, final. Be careful not to confuse definitive with definite. Definite means clearly defined. You can have a definite opinion that JFK could not have been assassinated by a lone gunman, but the definitive interpretation remains that of the Warren Commission Report, which held there was only one.

Example Sentences

See Examples For:

definitive

“Reuniting with Steve under a fully independent model allows us the creative control to honor what makes Jason the greatest slasher of all time and deliver the definitive theatrical event that today’s audiences expect.”

From Los Angeles Times ● Nov. 13, 2026

Now, research published in Science Advances provides definitive confirmation that the same two rocks, located in Mars' Bright Angel formation, contain organic carbon, an essential component of life.

From Science Daily ● Nov. 12, 2026

Patrice Chéreau’s 1976 Bayreuth centenary staging, for many still the cycle’s definitive modern vision, found a parable of industrial capitalism and class conflict inside Wagner’s myth.

From The Wall Street Journal ● Nov. 6, 2026

But with coal still the leading source of power generation, Turkey is under pressure to pair its impressive renewables growth with a definitive shift away from fossil fuels.

From Barron's ● Nov. 5, 2026

“Again, we don’t have definitive data, but it could be reduced to just a couple of years or maybe even less.”

From "The Adoration of Jenna Fox" by Mary E. Pearson

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Related Words

• actual
• categorical
• clear-cut
• conclusive
• decisive
• definite
• exhaustive
• precise
• reliable
• specific
• ultimate
• unambiguous

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