1. (n.) The act of encroaching upon the rights or possessions of another\; encroachment; trespass.

2. (n.) A warlike or hostile entrance into the possessions or domains of another; the incursion of an army for conquest or plunder.

3. (n.) The incoming or first attack of anything hurtful or pernicious; as, the invasion of a disease.

adoption aggression air attack air raid air strike appropriation arrogation assault assumption attack blitzkrieg boarding breach drive encroachment entrance entrenchment escalade fire raid foray impingement imposition incursion infestation infiltration influx infraction infringement injection inroad insinuation interference interjection interloping interposition interposure interruption intervention intrusion irruption lousiness obtrusion offense offensive onslaught overrunning overspreading overswarming plague playing God raid ravage razzia saturation raid scaling seizure shuttle raid storming swarm swarming teeming transgression trespass trespassing unlawful entry usurpation violation