1. The measurement of altitude or height, especially of aircraft, mountains, or celestial objects above a reference level such as sea level.
Usage: technical; commonly used in aviation, geography, and astronomy

Examples

• The pilot relied on altimetry instruments to maintain the correct flying altitude.
• Satellite altimetry has revolutionized our understanding of ocean surface topography.
• Modern aircraft use radar altimetry to measure their distance from the ground.
• The mountaineers used GPS altimetry to track their elevation gain during the climb.
• Altimetry data from space missions has improved weather forecasting models.
• The aircraft's altimetry system malfunctioned, requiring an emergency descent.