From Longman Dictionary of Contemporary Englishfrogmanfrog‧man /ˈfrɒɡmən $ ˈfrɑːɡ-, ˈfrɒːɡ-/ noun (plural frogmen /-mən/) [countable] British English TTWBOsomeone who swims under water using special equipment to help them breathe, especially as a job SYN diver Police frogmen have been searching the lake looking for a weapon.
Examples from the Corpus
frogman• The discovery sparked a full-scale search by more than 50 police and frogmen in Harpenden, Herts.• And frogmen have been dragging the River Severn near Hardwicke looking for clues.• Marines in camouflage fatigues and grease paint, along with a few frogmen, boarded three rubber boats for Yudo Island.• Allan McKay's body was recovered by police frogmen on 10 September.• At York University ... Police frogmen have been searching lakes looking for a weapon ... believed to be a six inch blade. 