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

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

The change in elevation from the waterfront at sea level to Genoa’s mountainous hinterland approaches 6,000 feet, and variations between adjoining neighborhoods can be as much as several hundred feet.

From The Wall Street Journal ● Aug. 23, 2026

Now their country, which is lower than sea level, finds itself, in an era of global warming, facing a dilemma: how to retain water while protecting themselves from it?

From Barron's ● Aug. 15, 2026

Her ranch, about 130 miles northeast of Higdon’s spread, sits at 10,000 feet above sea level, ideal for yaks who thrive in the state’s cool, alpine climate.

From Los Angeles Times ● Aug. 8, 2026

Or one could specify that a point was at a certain latitude and longitude and a certain height above sea level.

From "A Brief History of Time: And Other Essays" by Stephen Hawking

Related Words

• water level