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Definitions

deep-sea

[deep-see] / ˈdipˈsi /
ADJECTIVE
marine
Synonyms
STRONGEST
aquatic coastal maritime naval saltwater seagoing
STRONG
littoral nautical oceanic sea seafaring seashore seaside shore
WEAK
Neptunian abyssal hydrographic natatorial navigational ocean-going oceanographic pelagic
Antonyms
WEAK
freshwater
ADJECTIVE
marine/maritime
Synonyms
WEAK
Neptunian abyssal aquatic coastal hydrographic littoral natatorial nautical naval navigational oceangoing oceanic oceanographic of the sea pelagic saltwater sea seafaring seagoing seashore seaside shore
ADJECTIVE
maritime
Synonyms
STRONGEST
aquatic marine naval oceangoing seafaring seagoing
WEAK
oceanic pelagic
ADJECTIVE
nautical
Synonyms
STRONGEST
maritime navigational seafaring
STRONG
marine
WEAK
abyssal aquatic boating cruising naval navigating oceangoing oceanic oceanographic pelagic rowing sailing sailorly salty sea-loving seagoing ship thalassic yachting
ADJECTIVE
nautical/naval
Synonyms
WEAK
abyssal aquatic boating cruising marine maritime navigating navigational oceangoing oceanic oceanographic pelagic rowing sailing sailorly salty sea-loving seafaring seagoing thalassic yachting
ADJECTIVE
thalassic
Synonyms
WEAK
Neptunian abyssal aquatic coastal hydrographic littoral maritime natatorial nautical naval navigational oceangoing oceanic oceanographic of the sea pelagic saltwater sea seafaring seagoing seashore seaside shore

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The ship, also linked to the Kremlin’s deep-sea unit, has crisscrossed the globe for a decade mapping vital arteries for the global economy that run along the sea floor, Western officials say.

From The Wall Street Journal • Apr. 9, 2026

After graduating, she expanded the assignment into a full review comparing deep-sea vents and impact-generated systems.

From Science Daily • Apr. 3, 2026

"The affected area is of exceptional ecological value, with fragile deep-sea ecosystems and some of the highest biodiversity in the Mediterranean basin."

From Barron's • Mar. 15, 2026

The scientists examined genetic material collected from volcanic lakes in Iceland and from deep-sea hydrothermal vents located more than two kilometers beneath the North Atlantic Ocean.

From Science Daily • Mar. 14, 2026

“I know this place. We’re close. We have to go through the Orleans, to get to the deep-sea platforms. We’ll need a water taxi.”

From "Ship Breaker" by Paolo Bacigalupi