In*va"sion (?), n. [L. invasio:
cf. F. invasion. See Invade.]
1. The act of invading; the act of
encroaching upon the rights or possessions of another; encroachment;
trespass.
2. A warlike or hostile entrance into the
possessions or domains of another; the incursion of an army for
conquest or plunder.
3. The incoming or first attack of anything
hurtful or pernicious; as, the invasion of a
disease.
Syn. -- Invasion, Irruption, Inroad.
Invasion is the generic term, denoting a forcible entrance
into a foreign country. Incursion signifies a hasty and sudden
invasion. Irruption denotes particularly violent invasion.
Inroad is entry by some unusual way involving trespass and
injury.