1. Settling a matter or conflict; conclusive: the decisive battle in the war; the decisive piece of evidence in the lawsuit.
2. Characterized by or showing the ability to make decisions quickly and firmly; resolute: a decisive leader.
Synonyms: decisive, conclusive, critical, crucial, definitive, determinative
These adjectives mean determining an outcome or settling an issue with finality: the decisive vote; a conclusive reason; a critical experiment; a crucial moment; a definitive verdict; the determinative battle.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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