1. A warship intended for combat
   "The HMS Victory was a formidable man-of-war in the British Royal Navy";
   - ship of the line, man-o'-war
    
2. Large siphonophore having a bladderlike float and stinging tentacles
   "Swimmers were warned about Portuguese man-of-war in the area";
   - Portuguese man-of-war, jellyfish, man-o'-war

Derived forms: men-of-war

Type of: combat ship, siphonophore, war vessel, warship

Part of: genus Physalia, Physalia

Encyclopedia: Man-of-war