1. in a way that settles a matter conclusively or produces a definite result
2. in a confident and determined manner, without hesitation

Examples

• The team won decisively with a score of 45-12.
• She acted decisively when the emergency occurred.
• The evidence decisively proved his innocence.
• The CEO spoke decisively about the company’s future direction.
• The battle was won decisively by the allied forces.
• He decisively rejected the proposal without further discussion.