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

The department’s marine unit is now using an underwater drone to assess the wreckage and evaluate whether it is feasible to bring the boat to the surface.

From Los Angeles Times ● Jul. 18, 2026

Scientists have discovered that one of the most extreme volcanic events in Earth's history did more than build a massive underwater plateau.

From Science Daily ● Jul. 18, 2026

Their work has included underwater camera surveys, drone monitoring, analysing egg cases, and research with local anglers.

From BBC ● Jul. 11, 2026

Soon afterward, satellite observations confirmed that an underwater eruption was underway.

From Science Daily ● Jul. 10, 2026

The excavations of the Antikythera shipwreck, in 1900, marked the beginnings of underwater excavations carried out in what is regarded as a technologically primitive manner.

From "Shipwrecked!" by Martin W. Sandler

Related Words

• submerged
• undersea