1.
Something that exists or happens ~ exists or happens below the surface of the sea, a river, or a lake.
...giant submarines able to travel at high speeds ~...
Some stretches of beach are completely ~ at high tide...
ADV: ADV after v, n ADV
•
Underwater is also an adjective.
...~ exploration.
...a retired ~ photographer.
ADJ: ADJ n
2.
Underwater devices are specially made so that they can work in water.
...~ camera equipment.
...a pool of clear water lit by ~ lights.
ADJ: ADJ n