An instrument that measures the altitude of an aircraft or other object above a fixed level, such as sea level.
Late 19th century, from latin altus (high) + -meter (measure).
- The pilot checked the altimeter before take-off to ensure they were at the correct altitude.
- The altimeter showed that the aircraft was at an altitude of 30,000 feet.
- Altimeter is an essential instrument for aircraft navigation and safety.
- The altimeter is used to measure the height above sea level.
- The altitude of the mountain was measured using an altimeter.