invasion meaning and definition

INVASION noun

Definition of invasion (noun)

1. the act of invading; the act of an army that invades for conquest or plunder
2. any entry into an area not previously occupied
   • "an invasion of tourists"; "an invasion of locusts"
   • synonyms: encroachment, intrusion
3. (pathology) the spread of pathogenic microorganisms or malignant cells to new sites in the body
   • "the tumor's invasion of surrounding structures"