underwater

adjective

ˌən-dər-ˈwȯ-tər How to pronounce underwater (audio)
Definition of underwaternext
as in aquatic
living, lying, or occurring below the surface of the water underwater plants don't require as much light to grow as surface plants a vessel designed for underwater exploration

Synonyms & Similar Words

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Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of underwater The subs never actually submerged—passengers simply sat below the lagoon’s waterline—but the ride embodied a growing appetite for underwater tourism. — Bill Gourgey, Popular Science, 2 July 2026 The technology is an autonomous underwater vehicle (AUV) paired with its own seabed docking station. — New Atlas, 5 July 2026 Its tendency to rapidly reproduce, forming dense colonies on underwater surfaces, can clog pipes, pumps and critical water infrastructure while disrupting local ecosystems. — Reeti Malhotra, Sacbee.com, 4 July 2026 Other fun underwater activities include putting on swimming races or diving competitions or playing games like Marco Polo, Sharks and Minnows, or Red Light, Green Light. — Holly Lebowitz Rossi, Parents, 2 July 2026 See All Example Sentences for underwater
Recent Examples of Synonyms for underwater
  1. aquatic
  2. submarine
  3. submerged
Adjective
  • Part of the Splash Jelly Drop collection, Tory Burch’s Mini Romy reworks one of the brand’s signature shapes into a bright aquatic blue that immediately calls to mind swimming pools and cloudless skies.
    — Sanika Achrekar, Glamour, 2 July 2026
  • Research examining toxins and microplastics in aquatic environments has raised concerns about their potential effects on these microscopic organisms and the broader marine ecosystem.
    — Jason Phillips, USA Today, 2 July 2026
Definition of aquatic
Adjective
  • But a new antenna technology, borrowed from the physics of medical implants, is rethinking how submarine machines talk to each other – and to us.
    — Omar Kardoudi June 06, New Atlas, 6 June 2026
  • As a near-term step, the United States, Australia, and the United Kingdom should invite Japan to participate in discrete (non-submarine) elements of the 2021 AUKUS security pact, which will support Australia’s acquisition of nuclear submarines and promote cooperation on other advanced capabilities.
    — CHRISTOPHER JOHNSTONE, Foreign Affairs, 12 Jan. 2023
Definition of submarine
Adjective
  • The driver was found deceased inside her submerged vehicle hours after calling 911 for help.
    — Natassia Paloma, USA Today, 16 June 2026
  • This seemingly futuristic idea drew on his Navy experience with water-splitting electrolyzers, which supplied the oxygen that enabled subs to remain submerged for months at a time, and NASA’s use of hydrogen fuel cells to power the Apollo missions.
    — IEEE Spectrum, IEEE Spectrum, 15 June 2026
Definition of submerged

Browse Nearby Words

undervaluing
underwater
under way
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Cite this Entry

“Underwater.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underwater. Accessed 7 Jul. 2026.

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More from Merriam-Webster on underwater

Nglish: Translation of underwater for Spanish Speakers

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