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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.


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

    1. (of postage stamps) permanently on sale

    2. (as noun) a definitive postage stamp

"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

noun

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

"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

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)

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.

Keep Reading on Vocabulary.com

Vocabulary lists containing definitive

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.

Extreme efforts to “stage-manage” a student’s narrative can backfire, said Eric Tipler, author of “Write Yourself In: The Definitive Guide to Writing Successful College Admissions Essays.”

From The Wall Street Journal • Feb. 16, 2026

Mr. Haynes, of Portland, debuted in the W.W.F., which is today called World Wrestling Entertainment, in 1986, according to the book “WWE Encyclopedia: The Definitive Guide to World Wrestling Entertainment.”

From New York Times • Feb. 11, 2024

Definitive coins feature the standard designs seen on the majority of official currency.

From BBC • Oct. 12, 2023

Kendi’s 2019 bestseller “How to Be an Anti-Racist” surged in popularity, leading readers, including Williams, to his earlier 2016 National Book Award winner “Stamped From the Beginning: The Definitive History of Race in America.”

From Los Angeles Times • Aug. 30, 2023

Definitive list of things I want to do: 1.

From "Feed" by M.T. Anderson