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
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Water conditions, food sources and even the composition of the seafloor can influence their flavor and appearance. — Peter Burke, FOXNews.com, 17 Oct. 2026 Its retreat has altered the glacier’s geometry and relationship with the seafloor, meaning that simply reducing ocean melting may not restore its earlier state on century-long timescales. — Kaif Shaikh, Interesting Engineering, 17 Oct. 2026 But pollock often swim close to the seafloor, so the nets make substantial bottom contact. — Annika Hammerschlag, Los Angeles Times, 13 Oct. 2026 Comparisons of seafloor topography before and after the eruption showed that a roughly 4-kilometer-wide caldera sank by about a kilometer during the eruption. — Yook Ji Hun, ArsTechnica, 23 Sep. 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 20 Oct. 2026.

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Kids Definition

seafloor

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