- (not comparable) beneath the surface of the water, or of or pertaining to the region beneath the water surface
- (nautical) beneath the water line of a vessel
- (figuratively) Under water.
- (finance) having negative equity; owing more on an asset than its market value
- We've been underwater on our mortgage ever since the housing crash.
- German: unter Wasser, Unterwasser-
- Italian: subacqueo, sottacqua, sott'acqua
- Portuguese: submarino, subaquático, submarinho
- Russian: подво́дный
- Spanish: sumergido
- Italian: sott'acqua
underwater (plural underwaters)
- underlying water or body of water, for example in an aquifer or the deep ocean
- (fishing) A type of lure which lies beneath the water surface.
underwater (underwaters, present participle underwatering; past and past participle underwatered)
- (agriculture, horticulture) to water or irrigate insufficiently
- Care must be taken not to underwater houseplants in the summer.