Seamount

noun (countable)

/ˈsiːmaʊnt/

A submarine volcanic mountain rising at least 1,000 m above the surrounding ocean floor but not reaching the sea surface, typically of basaltic composition and conical or flat-topped (guyot) in form. Seamounts are biodiversity hotspots, concentrating nutrients and supporting unique deep-sea communities; Wessel, Sandwell and Kim predict that over 100,000 seamounts more than 1 km high remain uncharted. In the Indian Ocean, India's Deep Ocean Mission (launched on 7 September 2021) targets polymetallic nodules, which lie on the abyssal plains of the Central Indian Ocean Basin rather than on seamounts.

✍️ Usage in a UPSC answer

India's Deep Ocean Mission, launched on 7 September 2021 by the Ministry of Earth Sciences with an overall investment of ₹4,077 crore spread across five years (PIB, 17 Aug 2025), targets polymetallic nodules on the abyssal plains of the Central Indian Ocean Basin, sampled at depths such as 5,271 m.

Synonyms

submarine mountainunderwater volcanooceanic volcanoguyot (flat-topped variant)tablemount

Antonyms

oceanic trenchabyssal plainoceanic ridge (linear)submarine canyon

🌱 Word Family

seamount (noun), guyot (noun, flat-topped seamount), seamount chain (compound noun), hot-spot trail (related concept)

🔡 Root

Old English sæ = sea + Old English munt = mountain (from Latin mons); a compound of straightforward elements

📜 Etymology

A compound of Old English sæ (sea) and munt (mountain, from Latin mons/montis). The related term 'guyot' (flat-topped seamount) is credited to Harry Hess.

🧠 Memory Hook

SEA-MOUNT = a MOUNTAIN at SEA, but hidden underwater! Like an iceberg in reverse: the mountain is below the surface. Seamounts are ocean-floor giants that fish swim over but ships sail above without ever knowing.

🌍 Geography 📖 Seen in: Plate Tectonics and Volcanism…

Relevant across:GS1 · History, Geography & Society

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