seafloor

noun

sea·​floor ˈsē-ˌflȯr How to pronounce seafloor (audio)
variants or less commonly sea floor
plural seafloors also sea floors
: the floor of a sea or ocean : seabed
The Earth's crust, in this view, is divided into several immense plates that make up the continents and seafloors, and that all float on a hot, plastic, subterranean "mantle."Walter Sullivan

Examples of seafloor in a Sentence

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.
In the shallow reefs off the coast of southwestern Japan, a small fish scuttles along the rocky seafloor. Irene Wright, Miami Herald, 26 June 2025 In these marine habitats where sunlight can’t reach, gas escapes through cracks in the seafloor and feeds bacteria that latch on to the spiders’ exoskeletons. Jackie Wattles, CNN Money, 21 June 2025 In early March, the French Navy was conducting an exploratory deep-sea operation off southeastern France when sonar detected a large shape on the seafloor. Sarah Kuta, Smithsonian Magazine, 18 June 2025 Two large pieces of construction equipment — a compact loader called a skid steer and a 20-ton crane used for driving piles into the seafloor — tumbled into the water. Hailey Branson-Potts, Los Angeles Times, 8 June 2025 See All Example Sentences for seafloor

Word History

First Known Use

1853, in the meaning defined above

Time Traveler
The first known use of seafloor was in 1853

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Cite this Entry

“Seafloor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/seafloor. Accessed 6 Jul. 2025.

Kids Definition

seafloor

noun
sea·​floor -ˌflō(ə)r How to pronounce seafloor (audio)
-ˌflȯ(ə)r
: seabed

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