undersea

1 of 2

adjective

un·​der·​sea ˌən-dər-ˈsē How to pronounce undersea (audio)
1
: being or carried on under the sea or under the surface of the sea
undersea oil deposits
undersea fighting
2
: designed for use under the surface of the sea
an undersea fleet

undersea

2 of 2

adverb

variants or underseas
: under the sea : beneath the surface of the sea
photographs taken undersea

Examples of undersea in a Sentence

Adjective They are conducting undersea research.
Recent Examples on the Web
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.
Adjective
Unseen but crucial, undersea cables prop up internet services and communications, as well as many other aspects of daily life often taken for granted. Thomas G. Moukawsher, Newsweek, 20 Mar. 2025 In February 2023, two Chinese merchant vessels cut undersea cables connecting Taiwan’s main island with the Matsu Islands, disrupting Internet communications. Daniel Byman, Foreign Affairs, 13 Mar. 2025 Days after Trump's inauguration, an Italian company called the Prysmian Group cancelled plans to build a factory in Massachusetts that would have supplied undersea cables for offshore wind projects. Michael Copley, NPR, 12 Mar. 2025 Ahead of Trump’s executive order on wind, an Italian company abandoned plans to build a factory in Massachusetts to produce undersea cables to US offshore wind farms. Matt Egan, CNN, 10 Mar. 2025 See All Example Sentences for undersea

Word History

First Known Use

Adjective

1613, in the meaning defined at sense 1

Adverb

1645, in the meaning defined above

Time Traveler
The first known use of undersea was in 1613

Cite this Entry

“Undersea.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undersea. Accessed 29 Mar. 2025.

Kids Definition

undersea

adjective
un·​der·​sea
ˈən-dər-ˈsē
1
: being or carried on under the sea or under the surface of the sea
undersea oil deposits
undersea warfare
2
: designed for use under the surface of the sea
undersea fleet

More from Merriam-Webster on undersea

Last Updated: - Updated example sentences
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