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.
Crabs scuttle across the seafloor as water ripples around your feet. — Melissa Cristina Márquez, Forbes.com, 25 June 2026 Winds drive surface currents and much slower currents extend from the ocean’s surface down to the seafloor. — Janet Loehrke, USA Today, 15 June 2026 Bering Sea snow crab landings were down 84% in 2018 after a marine heat wave reached the seafloor. — Dillon Amaya, The Conversation, 12 June 2026 The zone then funnels carcasses to the seafloor, and very little sediment movement at those depths means that the carcasses stay exposed to scavengers. — Mindy Weisberger, CNN Money, 12 June 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

See All Rhymes for seafloor

Browse Nearby Words

sea flea
seafloor
seafloor spreading
See all Nearby Words

Cite this Entry

“Seafloor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/seafloor. Accessed 7 Jul. 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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