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Synonyms

decisive

American  
[dih-sahy-siv] / dɪˈsaɪ sɪv /

adjective

  1. having the power or quality of deciding; putting an end to controversy; crucial or most important.

    Your argument was the decisive one.

    Synonyms:
    final, conclusive
  2. characterized by or displaying no or little hesitation; resolute; determined.

    The general was known for his decisive manner.

    Synonyms:
    firm
  3. indisputable; definite.

    a decisive defeat.

  4. unsurpassable; commanding.

    a decisive lead in the voting.


decisive British  
/ dɪˈsaɪsɪv /

adjective

  1. influential; conclusive

    a decisive argument

  2. characterized by the ability to make decisions, esp quickly; resolute

"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 decisive

First recorded in 1605–15; from Medieval Latin dēcīsīvus, equivalent to Latin dēcīs(us) ( see decision) + -īvus adjective suffix ( see -ive)

Explanation

If you make decisions quickly, you are someone who is decisive. A decisive event can settle something, like a war. People who are wishy-washy are the opposite of decisive: being decisive means you don't waffle or take forever to make up your mind, and then you stick by what you decided. People admire politicians, coaches, and friends who are decisive. In sports, if a home run won the game, that was the decisive run. When you reach a crisis point in life — when things are going to change one way or the other — you've reached a decisive moment.

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Vocabulary lists containing decisive

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.

“When allegations are reported, they are promptly reviewed, and appropriate interim measures are implemented to protect those involved. If violations are substantiated, the District takes decisive action in accordance with the law and our policies.”

From Los Angeles Times • May 5, 2026

“That is unacceptable, and we are taking decisive action to hold them accountable.”

From Los Angeles Times • May 4, 2026

Conflicts that begin with strikes from far away tend to shift, in their decisive phases, to questions of land control: Who holds certain terrain, who secures the population, who can enforce order.

From The Wall Street Journal • May 3, 2026

And as the season enters its decisive part, this talented but under-the-radar forward could prove crucial in the Gunners' quest for silverware.

From BBC • May 2, 2026

The end of the Ice Age was accompanied by the first of the two most decisive changes in Japanese history: the invention of pottery.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond