- the horizontal plane or level corresponding to the surface of the sea at mean level between high and low tide.
Origin of sea level
First recorded in 1800–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for sea level
But with the sea-level rise, a 10-year storm could have the same effect.The MTA and New York City Will Get Hit Again
November 3, 2012
The height of a mountain on the earth is stated to be so much above the sea-level.Aether and Gravitation
William George Hooper
Physically speaking, however, we need not go below the sea-level.Fragments of science, V. 1-2
This species has been seen as high as 5000 feet above the sea-level.
This has been seen as high as 5500 feet above the sea-level.
The normal air-pressure at sea-level on our bodies or any other objects is about 15 lbs.How it Works
- 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
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- 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.♦ 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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