Quick definitions from WordNet (invade)
▸ verb: occupy in large numbers or live on a host
▸ verb: march aggressively into another's territory by military force for the purposes of conquest and occupation ("Hitler invaded Poland on September 1, 1939")
▸ verb: penetrate or assault, in a harmful or injurious way ("The cancer had invaded her lungs")
▸ verb: to intrude upon, infringe, encroach on, violate ("This new colleague invades my territory")
▸ Also see invade
▸ verb: occupy in large numbers or live on a host
▸ verb: march aggressively into another's territory by military force for the purposes of conquest and occupation ("Hitler invaded Poland on September 1, 1939")
▸ verb: penetrate or assault, in a harmful or injurious way ("The cancer had invaded her lungs")
▸ verb: to intrude upon, infringe, encroach on, violate ("This new colleague invades my territory")
▸ Also see invade