1. An attack that penetrates into enemy territory
   "The special forces made a deep incursion behind enemy lines";
   - penetration
    
2. The act of entering some territory or domain (often in large numbers)
   "the incursion of television into the American living room"
    
3. The act of becoming involved in or responsible for something problematic
   "His incursion into debt happened gradually"

Derived forms: incursions

Type of: attack, entrance, entry, error, fault, incoming, ingress, mistake, onrush, onset, onslaught

Encyclopedia: Incursion, Part 2