Average height of the surface of the sea for all stages of the tide over a 19-year period. NOTE: when the abbreviation MSL is used in conjunction with a number of feet, it implies altitude above sea l [..]

(MSL) - The arithmetic mean of hourly water elevations observed over a specific 19-year tidal epoch.

(Abbreviated MSL; popularly called sea level.) The arithmetic mean of hourly heights observed over some specified period. In the United States, mean sea level is defined as the mean height of the surf [..]

The average height of the surface of the sea for all stages of tide. 

The average level of the ocean's surface, as measured by the level halfway between mean high and low tide. Used as a standard in determining land elevation or sea depths.

see MSL

The average (arithmetic mean) height of the surface of the sea for all stages of tide, observed hourly over a 19-year cycle, with reference to a suitable reference surface or datum, called the geoid. [..]

This is a common frame of reference for positions with a vertical component. The average location at which the ocean meets the beach is considered “mean sea level”.

According to 44 CFR 59.1 (Title 44 - Emergency Management And Assistance; Chapter I - Federal Emergency Management Agency, Department Of Homeland Security; Subchapter B - Insurance And Hazard Mitigati [..]

The average height of the sea-surface.

Tidal datum that is the arithmetic mean of the hourly water elevations observed over a specific 19-year Metonic cycle (National Tidal Datum Epoch). Shorter series are specified in the name; that is, m [..]

The average height of the sea surface, based upon hourly observation of the tide height on the open coast or in adjacent waters that have free access to the sea. In the United States, it is defined as the average height of the sea surface for all stages of the tide over a nineteen year period. Mean sea level, commonly abbreviated as MSL and referre [..]

MSL is a measure of the average height of the ocean’s surface (such as the halfway point between the mean high tide and the mean low tide); used as a standard in reckoning land elevation.

The average level of the sea surface over a long period, previously 18·6 years, or the average level which would exist in the absence of tides.

(MSL)

Is the level water surface (or "still water level"), measured with respect to some datum, when oscillatory motions such as waves and tides have been averaged out over a suitable period (e.g. [..]

Standard aviation term See Also: above sea level;

The average height of the sea surface water level. For the United States , it is computed by averaging the levels of all tide stages over a ninteen year period, determined from hourly height readings [..]

The average height of the sea surface water level. For the United States , it is computed by averaging the levels of all tide stages over a nineteen year period, determined from hourly height readings [..]

The average height of the surface of the sea for all stages of the tide over a 19-year period, usually determined from hourly height readings (see sea level datums).

Level that sea would maintain if no tidal effect were manifested and average meteorological conditions pre­vailed. For hydrographic and surveying purposes the level is derived from very prolonged and [..]

a reference point used as a standard for determining terrestrial and atmospheric elevation or ocean depths and calculated as the average of hourly tide levels measured by mechanical tide gauges over e [..]

The average height of the sea surface, based upon hourly observation of the tide height on the open coast or in adjacent waters that have free access to the sea. In the United States, it is defined as [..]

Mean sea level (German – Normalnull, NN) is a reference point for standardizing measures of elevation in Germany, Switzerland and Austria. It is equal to the average elevation of sea level. This point [..]

The average height of the surface of the sea at a particular location for all stages of the tide over a 19-year period. This is usually determined from the hourly height readings of the tide gage at that site.

The average height of the sea with respect to historical data.

the time-averaged level of the ocean's surface and by geopotential extrapolation to land-covered areas; see also global mean sea level (GMSL)

  Average height of the surface of the sea for all stages of the tide; used as a reference for elevations.

The average height of the surface of the sea for all stages of tide; used as reference for elevations throughout the U.S.

Standard aviation term See Also: above sea level;

(MSL) - The arithmetic mean of hourly water elevations observed over a specific 19-year tidal epoch.

The average height of the surface of the sea for all stages of the tide over a 19-year period, usually determined from hourly height readings. Not necessarily equal to mean tide level. It is also the [..]

The average height of the sea surface water level. It is used as a basis for determining elevations, as the reference for all altitudes in upper air measurements, and as the level above which altitude [..]

(MSL

The average height of the sea surface water level. For the United States, it is computed by averaging the levels of all tide stages over a nineteen year period, determined from hourly height readings measured from a fix, predetermined reference level. It is used as a basis for determining elevations, as the reference for all altitudes in upper air [..]

The average height of the sea surface water level. For the United States, it is computed by averaging the levels of all tide stages over a nineteen year period, determined from hourly height readings [..]

The average height of the sea surface water level. For the United States, it is computed by averaging the levels of all tide

Mean sea level (MSL) is the average (mean) height of the sea, with reference to a suitable reference surface. Defining the reference level, however, involves complex measurement, and accurately determining MSL can prove difficult. See: Wikipedia explanation

The average height of the sea surface water level. For the United States, it is computed by averaging the levels of all tide stages over a nineteen year period, determined from hourly height readings measured from a fix, predetermined reference level. It is used as a basis for determining elevations, as the reference for all altitudes in upper air [..]

Elevation datum referenced to averaged sea level observations over an extended period of time.

  Elevation datum referenced to averaged sea level observations over an extended period of time.