From Longman Dictionary of Contemporary Englishunderwaterun‧der‧wa‧ter /ˌʌndəˈwɔːtə◂ $ ˌʌndərˈwɒːtər◂, -ˈwɑː-/ ●●○ adjective [only before noun] UNDER/BELOWbelow the surface of an area of water, or able to be used there an underwater camera —underwater adverb He dived underwater and swam away.
Examples from the Corpus
underwater• Are some renowned amongst their fellows for the quality of their underwater ballads and harmonies?• Monterey Bay in northern California is an underwater canyon about the size and depth of the Grand Canyon.• The grass simply evolves into underwater grass and seems to exist equally comfortably waving dreamily around, endlessly drowning.• He could not tell whether they were broken ends, or perhaps the loose ends from underwater knots that had come undone.• Each guide also includes full colour underwater photographs illustrating the marine life you could expect to see.• underwater plants• The Weathermatic happily bobbed about in mountain pools, the automatic flash adding sparkle to underwater shots. 