Altimeter

Science / Weather / Altimeter: An instrument used to determine the altitude of an object with respect to a fixed level. The type normally used by meteorologists measures the altitude with respect to sea level pressure.
Search Google for Altimeter:

Altimeter Setting

Technology / Aviation / Altimeter Setting: A reference setting on the altimeter so that the instrument indicates an accurate altitude. MORE

Radar Altimeter

Technology / Radar / Radar Altimeter: A radar altimeter is used by an aircraft to determine its height above terrain. MORE

Pressure Altimeter

Science / Weather / Pressure Altimeter: An aneroid barometer calibrated to indicate altitude in feet instead of units of pressure. It is read accurately only in a standard atmosphere and when the correct altimeter setting is used. MORE

Metar

Technology / Aviation / Metar: Acronym in FAA pilot briefings and weather reports simply means an 'aviation routine weather report,' but nobody seems certain about the original source. The format was introduced by the French on 1 J MORE

Mean Sea Level

Science / Weather / Mean 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 nineteen year period, determined from hourly height readings MORE

Pressure Altitude

Science / Weather / Pressure Altitude: The altitude in standard atmosphere at which a given pressure will be observed. It is the indicated altitude of a pressure altimeter at an altitude setting of 29.92 inches of mercury, and is therefore MORE