1. an instrument that measures altitude or height above sea level
Usage: aviation; mountaineering

Examples

• The pilot checked the altimeter before beginning the descent.
• Mountain climbers use an altimeter to track their elevation.
• The aircraft’s altimeter showed they were flying at 30,000 feet.
• She calibrated her altimeter at base camp before the climb.
• The altimeter reading indicated they had reached the summit.
• Modern altimeters use barometric pressure to determine altitude.