scu ‧ ba div ‧ ing /ˈskuːbə ˌdaɪvɪŋ/ BrE AmE noun [uncountable]
[ Date: 1900-2000 ; Origin: self-contained underwater breathing apparatus ]
the sport of swimming under water while breathing through a tube that is connected to a container of air on your back
—scuba diver noun [countable]