subaqueous

Existing below the water surface.

subaqueous deposits

Designed for underwater use.

a subaqueous helmet

Weak and filtered.

subaqueous light

The room was dimly lit by a subaqueous light filtering through a green blind, and Rita had to edge her way round a double bed that barely allowed room to reach a bedside table, for the room, like every other apartment in the house, was clogged with old furniture.