decisive
adjective/dɨsiˈzivʊ/high
de·ci·si·vo
Definition
That determines or resolves a situation; of crucial importance for the outcome.
His support was decisive for the project's success.
The decisive moment of the match was the last goal.
Common collocations
decisive momentdecisive roledecisive votedecisive factor
Etymology
Do latim 'decisivus', de 'decidere' (decidir).