underwater

American  

[uhn-der-waw-ter, -wot-er] / ˈʌn dərˈwɔ tər, -ˈwɒt ər /

adjective

1. existing or occurring under water.

2. designed to be used under water.

3. located below a ship's waterline.

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adverb

1. beneath the water.

   to travel underwater.

noun

1. the water beneath the surface.

   cold currents in the underwater.

2. underwaters, the depths, as of a sea, lake, etc.

underwater British  

/ ˈʌndəˈwɔːtə /

adjective

1. being, occurring, or going under the surface of the water, esp the sea

   underwater exploration

2. nautical below the water line of a vessel

3. (of a stock option or other asset) having a market value below its purchase value

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adverb

1. beneath the surface of the water

Etymology

Origin of underwater

First recorded in 1620–30; under- + water

Example Sentences

See Examples For:

underwater

Next, we surveyed the structures with an underwater drone and the Deep Sea Camera System.

From Science Daily ● Sep. 15, 2026

The US military said one of its underwater drones "malfunctioned" and was not carrying any sensitive data.

From Barron's ● Sep. 8, 2026

The underwater drone, tethered to the ship with cables and about the size of a small car, was just above the ocean floor as the researchers and pilots searched for furrows potentially left by whales.

From Los Angeles Times ● Sep. 5, 2026

Steve Irwin died on 4 September 2006, aged 44, after a stingray fatally pierced his chest while he was underwater filming a documentary at the Great Barrier Reef.

From BBC ● Sep. 4, 2026

Among many other revelations, the underwater discoveries at Antikythera, Cape Gelidonya, and Uluburun led to vital new information about the nature of ships and maritime trading in the ancient Mediterranean world.

From "Shipwrecked!" by Martin W. Sandler

Related Words

• submerged
• undersea