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

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Part of that effort included setting up a waterproof data center on the seafloor near Scotland’s Orkney Islands in 2018. — Nir Kshetri, The Conversation, 17 Aug. 2026 Fossil collectors report finding the teeth in coastal rivers or along seafloor ledges that have been scoured by storms and currents. — Mark Price, Charlotte Observer, 16 Aug. 2026 The process of hydraulic fracturing ekes out oil from older wells, and involves cracking the bedrock several thousand feet below the seafloor by injecting chemical fluids with intense pressure. — Rosanna Xia, Los Angeles Times, 14 Aug. 2026 In 2024, a group of scientists reported that lumps of metal on the Pacific seafloor—which happened to be the target of seabed-mining operations—seemed to be producing dark oxygen. — James Dinneen, New Yorker, 13 Aug. 2026 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

Phrases Containing seafloor

Rhymes for seafloor

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Browse Nearby Words

sea flea
seafloor
seafloor spreading
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Cite this Entry

“Seafloor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/seafloor. Accessed 22 Aug. 2026.

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Kids Definition

seafloor

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

More from Merriam-Webster on seafloor

Nglish: Translation of seafloor for Spanish Speakers

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