From BiblePortal Wikipedia

King James Dictionary [1]

Inva'Sion, n. s as z. L. invasio, from invado. See Invade.

1. A hostile entrance into the possessions of another particularly, the entrance of a hostile army into a country for the purpose of conquest or plunder, or the attack of a military force. The north of England and south of Scotland were for centuries subject to invasion, each from the other. The invasion of England by William the Norman, was in 1066. 2. An attack on the rights of another infringement or violation. 3. Attack of a disease as the invasion of the plague, in Egypt.

Webster's Dictionary [2]

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

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

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