[adj] 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"
[adj] marked by aggressive ambition and energy and initiative; "an aggressive young exective"; "a pushful insurance agent"; "a pushing youth intent on getting on in the world"
[adj] characteristic of an enemy or one eager to fight; "aggressive acts against another country"; "a belligerent tone"
[adj] tending to spread quickly; "an aggressive tumor"
ambitious, assertive, battleful, bellicose, belligerent, combative, competitive, contentious, enterprising, fast-growing(a), hard-hitting, high-pressure, hostile, invasive, militant, obstreperous, predatory, pugnacious, pushful, pushing, pushy, rapacious,