What does "ocean" mean?

1. (large body of water) one of the five huge areas of salt water on Earth, like the Atlantic or Pacific. 2. (a vast amount) a very large amount or a huge space of something. 3. (mythology) in ancient Greek stories, the great river that people believed flowed around the world.

ocean — meaning, definition & examples

Word

01large body of water

A2 · Elementary Countable noun

n. one of the five huge areas of salt water on Earth, like the Atlantic or Pacific.

n. one of the major bodies of salt water into which the global hydrosphere is divided.

“The ship spent two weeks crossing the Atlantic Ocean during the summer.”

“Marine biologists are concerned that rising temperatures in the Southern Ocean could disrupt the migratory patterns of several whale species.”

Synonyms

sea

Antonyms

land

02a vast amount

B2 · Upper Intermediate Plural noun

n. a very large amount or a huge space of something.

n. an immense expanse or a vast quantity of something, often used figuratively.

“Looking out from the mountain top, he saw an ocean of green trees.”

“The candidate faced an ocean of criticism following the publication of the controversial report on urban planning.”

Synonyms

expanse sea abundance

Antonyms

drop bit

03mythology

C2 · Proficiency Uncountable noun Religion Literary

n. in ancient Greek stories, the great river that people believed flowed around the world.

n. the personification of the world-river in Greek mythology, often referred to as Oceanus.

“Ancient maps often showed Ocean as a river circling the entire earth.”

“In Homeric epic, Ocean is depicted not as a sea, but as the generative source of all gods and rivers.”

Synonyms

Oceanus

Common phrases and expressions where native English speakers use the word “ocean” in context.

01. ocean surface 02. ocean temperatures 03. ocean currents 04. ocean floor 05. ocean water 06. ocean waters

“A record-breaking 23 zettajoules of heat was sunk into the world’s seas last year, leaving ocean waters hotter, higher and less hospitable, a report has found.”

The Guardian 30 Sept 2026

“The world’s oceans are under “severe and accelerating” pressure from human activities, with the rate of sea-level rise double that of a decade ago, according to a damning assessment from the United Nations.”

The Guardian 8 Jun 2026

“China is conducting a vast undersea mapping and monitoring operation across the Pacific, Indian and Arctic oceans, building detailed knowledge of marine conditions that naval experts say would be crucial for waging submarine warfare against the United States and its allies.”

Reuters 24 Mar 2026

From Middle English *ocean, occean, occian, occyan, from Old French occean (later reborrowed or reinforced by Middle French ocean), from Latin Ōceanus, originally from Ancient Greek Ὠκεανός (Ōkeanós, “Oceanus”, a water deity). Displaced native Old English gārseċġ. Also commonly referred to as the ocean sea, the sea of ocean (compare Latin mare ōceanum; Old French mer oceane, occeanne mer). Compare Saterland Frisian Oceoan (“ocean”), West Frisian oseaan (“ocean”), Dutch oceaan (“ocean”), German Low German Ozeaan (“ocean”), German Ozean (“ocean”), Danish ocean (“ocean”), Swedish ocean (“ocean”), French océan (“ocean”), Italian oceano (“ocean”). Doublet of Oceanus/Okeanos.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

NOUN

ocean(A2)

oceanography(C1)

ADJECTIVE

oceanic(B2)

geography hydrographic lake ocean liner pelagic sea vastness