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 team collected samples and filmed the plume with an underwater drone to make a three-dimensional map. — Alec Luhn, Scientific American, 20 Oct. 2026 The world’s first demonstration of a subsea geothermal power plant has taken place near an active underwater volcano almost a mile below the ocean surface. — Jeremy Hsu, ArsTechnica, 19 Oct. 2026 Future versions would also feature a broader array of sensors such as underwater sensors and sonar, as well as larger energy-storage systems. — New Atlas, 17 Oct. 2026 The water level of the 90-year-old reservoir has dropped, exposing areas that were previously underwater. — CBS News, 16 Oct. 2026 See All Example Sentences for underwater
Recent Examples of Synonyms for underwater
  1. aquatic
  2. submarine
  3. submerged
Adjective
  • The motorcycle operates differently from a conventional watercraft, which typically uses a dedicated propulsion system designed for aquatic environments.
    — Jijo Malayil, Interesting Engineering, 26 Oct. 2026
  • The other two organizations focus on protecting waterways and aquatic ecosystems, including the Harpeth River, where Janson lives.
    — Amber Harding OutKick, FOXNews.com, 19 Oct. 2026
Definition of aquatic
Adjective
  • The third pillar expands on this approach by increasing the capacity of the wider submarine industrial base.
    — Georgina Jedikovska, Interesting Engineering, 22 Sep. 2026
  • 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
Definition of submarine
Adjective
  • The discovery was made in the submerged royal harbor of Alexandria, Egypt, and announced this month by the European Institute for Underwater Archaeology.
    — Andrea Margolis, FOXNews.com, 18 Oct. 2026
  • Advanced blue-green optical communications penetrate the water column to communicate with submerged submarines without requiring them to deploy compromise-prone antennas.
    — Rohit Jha, Forbes.com, 1 Oct. 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 29 Oct. 2026.

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