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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

  • decisively adverb
  • decisiveness noun
  • nondecisive adjective
  • predecisive adjective

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.

Keep Reading on Vocabulary.com

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.

The Argentine's first half-header, planted firmly past Lucas Perri after 23 minutes, turning out to be the decisive moment.

From BBC • Apr. 26, 2026

Katayama said that recent yen movements are speculative and that the authorities will take decisive action in the currency market if needed.

From The Wall Street Journal • Apr. 24, 2026

In the Islamic Republic's system, that position is meant to be decisive.

From BBC • Apr. 24, 2026

The next phase is usually a decisive, confirmed breakout.

From Barron's • Apr. 22, 2026

However, a voice responded at once, a crisp, decisive voice that sounded as though it were reading a prepared statement.

From "Harry Potter and the Half-Blood Prince" by J.K. Rowling