blue hole
blue hole · blue holes
A submarine cave or sinkhole, a roughly circular, steep-walled depression that is…A submarine cave or sinkhole, a roughly circular, steep-walled depression that is typically anoxic below a certain depth.
Meaning
1 sensesA submarine cave or sinkhole, a roughly circular, steep-walled depression that is typically anoxic below a certain depth.
Dictionary text adapted from Wiktionary (Wiktionary contributors, CC BY-SA 4.0) and Open English WordNet / Princeton WordNet (CC BY 4.0, WordNet License); shared under CC BY-SA 4.0. Example sentences and recordings are credited where they appear.