sea level

American  

noun

• sea levels
  plural

1. the horizontal plane or level corresponding to the surface of the sea at mean level between high and low tide.

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sea level British  

noun

1. the level of the surface of the sea with respect to the land, taken to be the mean level between high and low tide, and used as a standard base for measuring heights and depths

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sea level Scientific  

1. The level of the ocean's surface. Sea level at a particular location changes regularly with the tides and irregularly due to conditions such as wind and currents. Other factors that contribute to such fluctuation include water temperature and salinity, air pressure, seasonal changes, the amount of stream runoff, and the amount of water that is stored as ice or snow.

2. ◆ The reference point used as a standard for determining terrestrial and atmospheric elevation or ocean depths is called the mean sea level and is calculated as the average of hourly tide levels measured by mechanical tide gauges over extended periods of time.

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Other Word Forms

Noun Inflected Forms

• sea levels
  plural

Etymology

Origin of sea level

First recorded in 1800–10

Example Sentences

See Examples For:

sea level

By redistributing enormous amounts of heat through the Atlantic, it helps shape regional temperatures, rainfall patterns, sea level, and weather.

From Science Daily ● Sep. 23, 2026

Its transport of heat helps influence temperatures in Europe and North America, while also affecting rainfall, storms, and sea level.

From Science Daily ● Sep. 23, 2026

Around that time, unknown to anyone, a cluster of small lakes atop the Purepu Glacier, nearly 17,000 feet above sea level, had begun growing.

From The Wall Street Journal ● Sep. 9, 2026

And they can stack on top of each other: So it might be that the temporary sea level rise from one of these Kelvin waves doesn’t fully decline before the next peak arrives,” Swain said.

From Los Angeles Times ● Sep. 9, 2026

At the one extreme was Henderson Island, an old coral reef raised above sea level and devoid of stone Other than limestone.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

Related Words

• water level