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.

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decisive British  

/ dɪˈsaɪsɪv /

adjective

1. influential; conclusive

   a decisive argument

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

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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) ( decision ) + -īvus adjective suffix ( -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.

Example Sentences

Mince the hard-boiled eggs cleanly — decisive cuts, not frantic mashing.

From Salon • Apr. 14, 2026

Last month, Mladenov told the UN Security Council that "the laying down of arms by militant actors would represent a decisive break from cycles of violence that have defined life in Gaza for decades".

From BBC • Apr. 14, 2026

But Tehran remains defiant on this issue and it will be a decisive one in the looming negotiations between the US and Iran in Islamabad.

From BBC • Apr. 9, 2026

"This signal that the threat to international waterways can pass without any decisive action by the international organization responsible for the maintenance of international peace and security," he said.

From Barron's • Apr. 7, 2026

“I think something decisive will happen in the spring,” he said.

From "My Brother Sam is Dead" by James Lincoln Collier and Christopher Collier

Related Words

• conclusive
• critical
• crucial
• definitive
• determined
• fateful
• forceful
• influential
• momentous
• positive
• resolute
• significant