Word origin · etymology
Latin through Middle English.
Latin altitudo means height, from altus, high. Astronomical altitude preserves this vertical sense as an angle above the horizon.
How we know · epistemology
Local observational geometry
Altitude is calculated relative to a local horizon. Atmospheric refraction changes apparent altitude near the horizon, so a geometric result and an observed sighting need not coincide exactly.
Connected concepts
Browse other concepts in Astronomy & coordinates →
These links connect subjects and terminology. They do not establish a shared historical origin.
Sources & provenance
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