sea·​floor | \ ˈsē-ˌflȯr How to pronounce seafloor (audio) \
variants: or less commonly sea floor
plural seafloors also sea floors

Definition of seafloor

: 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 Sargassum also grows without needing to be attached to the seafloor or some other structure and has a very high ratio of stored carbon to other nutrients. Erik Kobayashi-solomon, Forbes, 7 June 2022 For example, the scientists found dolphins who live in regions with more seagrass have signature whistles that are higher in pitch and shorter in length when compared to those who live in areas where the seafloor is muddier. Sarah Sloat, NBC News, 26 May 2022 The ghost fossils were created as seafloor sediment turned into rock. Ashley Strickland, CNN, 19 May 2022 Other studies show that permafrost under the ocean itself is thawing, reshaping the seafloor, forming craters the size of city blocks and elevating new pingos. Lois Parshley, Anchorage Daily News, 3 May 2022 At some point—the when and why remain a mystery—the larvacean discards it, to the delight of scavengers waiting on the seafloor below. The New Yorker, 15 Apr. 2022 The cost of the SLS seems so egregious because each multibillion-dollar rocket will be discarded after a single use, its components relegated to junk on the seafloor or adrift in space. Jonathan O'callaghan, Scientific American, 12 Apr. 2022 In recent surveys, Salazar and his colleagues also found geological evidence of an earthquake and tsunami that struck the region: layers of sandy, shell-laden seafloor sediment lifted several meters above sea level by seismic upheaval. Kiona N. Smith, Ars Technica, 7 Apr. 2022 However, a new study recently mapped out portions of the Arctic seafloor. Joshua Hawkins, BGR, 30 Mar. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'seafloor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of seafloor

1853, in the meaning defined above

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The first known use of seafloor was in 1853

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Dictionary Entries Near seafloor

sea flea


seafloor spreading

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Last Updated

15 Jun 2022

Cite this Entry

“Seafloor.” Dictionary, Merriam-Webster, Accessed 6 Jul. 2022.

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More from Merriam-Webster on seafloor

Nglish: Translation of seafloor for Spanish Speakers


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