Quick definitions from WordNet (aggressive)
▸ adjective: characteristic of an enemy or one eager to fight ("Aggressive acts against another country")
▸ adjective: tending to spread quickly ("An aggressive tumor")
▸ adjective: having or showing determination and energetic pursuit of your ends ("An aggressive businessman")
▸ adjective: marked by aggressive ambition and energy and initiative ("An aggressive young exective")
▸ Also see aggressive
▸ adjective: characteristic of an enemy or one eager to fight ("Aggressive acts against another country")
▸ adjective: tending to spread quickly ("An aggressive tumor")
▸ adjective: having or showing determination and energetic pursuit of your ends ("An aggressive businessman")
▸ adjective: marked by aggressive ambition and energy and initiative ("An aggressive young exective")
▸ Also see aggressive