Diver (7)
'diver' is the definition.
(synonyms)
This is all the clue.
(Other definitions for frogman that I've seen before include "Rubber-suited diver" , "Underwater diver" , "Swimmer working underwater" , "Male diver" , "Swimmer employed in underwater operations" .)
'diver' is the definition.
(scuba diver is a kind of diver)
This is the entire clue.
(Other definitions for scuba that I've seen before include "Device that lets divers breathe under water" , "Skin-diving apparatus" , "Aqualung" , "Diving equipment" , "Diving apparatus" .)