- the height of an object or point in relation to sea level or ground level；great height
noun: altitude, plural noun: altitudes
- 1. the height of an object or point in relation to sea level or ground level flight data including airspeed and altitude flying at altitudes over 15,000 feet
- ▪ great height the mechanism can freeze at altitude
- ▪ the apparent height of a celestial object above the horizon, measured as an angle.
- ▪ the length of the perpendicular line from a vertex to the opposite side of a figure.