Answer: oceanaut

AnswerCrossword Clue
OCEANAUTSealab resident
OCEANAUTUndersea explorer
OCEANAUTSealab dweller
OCEANAUTSkin-diver
OCEANAUTUnderwater explorer
OCEANAUTSealab inhabitant
oceanautan aquanaut (a skin-diver)
oceanautaquanaut