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

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

Because of that role, changes in its stability could have implications for sea level rise.

From Science Daily ● Sep. 4, 2026

The glacier in question lies to the north of Langtang Lirung, a peak more than 7,000 metres above sea level in the Himalayas.

From BBC ● Aug. 27, 2026

A rare convergence of a powerful El Niño, super king tides and sea level rise spurred by climate change could menace California with record coastal flooding this winter.

From Los Angeles Times ● Aug. 24, 2026

A hug from Mom hadn’t fixed it, but it had pulled Cat’s heart from the bottom of the Mariana Trench to somewhere around sea level.

From "Caterpillar Summer" by Gillian McDunn

Related Words

• water level