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
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Adjective
The previous month, two undersea cables in the Baltic Sea were disrupted in quick succession. Kevin Lynn, Newsweek, 8 Jan. 2025 Although the undersea cable was damaged, Chunghwa Telecom was able to reroute internet communications through backups. Michael Kan, PCMAG, 7 Jan. 2025 In 2023, the outlying Matsu Islands, within view of the Chinese coast, endured patchy internet for months after two undersea internet cables broke. Meaghan Tobin, New York Times, 7 Jan. 2025 The coast guard had said on Saturday that a ship registered both to Cameroon and Tanzania was suspected of damaging an undersea communications cable northeast of the island. Reuters, NBC News, 7 Jan. 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

Dictionary Entries Near undersea

Cite this Entry

“Undersea.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undersea. Accessed 18 Jan. 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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