A frogman is someone who is trained in scuba diving or swimming underwater in a tactical capacity that includes combat. Such personnel are also known by the more formal names of combat diver, combatant diver, or combat swimmer.
In the U.S. military and intelligence community, divers trained in scuba or CCUBA who deploy for tactical assault missions are called "combat divers". This term is used to refer to the Navy SEALs, operatives of the CIA's Special Activities Division, elements of Marine Recon, Army Ranger Regimental Reconnaissance Company members, Army Special Forces divers, Air Force Pararescue, Air Force Combat Controllers, U.S. Coast Guard Helicopter Rescue Swimmers, United States Naval Search and Rescue Swimmers, United States Air Force Special Operations Weather Technicians, and the Navy Explosive Ordnance Disposal(EOD) units. In Britain, police divers have often been called "police frogmen".