1. Elevation especially above sea level or above the earth's surface
   "the altitude gave her a headache";
   - height
    
2. The perpendicular distance from the base of a geometric figure to the opposite vertex (or side if parallel)
   "The altitude of the triangle determined its area"
    
3. Angular distance above the horizon (especially of a celestial object)
   "The star's altitude was measured at 45 degrees";
   - elevation, EL, ALT

Derived forms: altitudes

Type of: angular position, distance, elevation, length

Encyclopedia: Altitude, effects on humans