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

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

Part of: genus Physalia, Physalia

Encyclopedia: Man-o'-war