əˈɡɹɛs.ɪv bəˈlɪdʒ.(ə).ɹənt bəˈlɪdʒ.ə.ɹənt having or showing determination and energetic pursuit of your ends an aggressive businessman an aggressive basketball player he was aggressive and imperious; positive in his convictions aggressive drivers characteristic of an enemy or one eager to fight aggressive acts against another country a belligerent tone tending to spread quickly an aggressive tumor