D defs.my
Entry 6 senses Webster, 1913

Altitude

/ăl'-tət-o͞odˌ/ · Al·ti·tude · IPA /ˈælt.ɪˌtjuːd/
01 n. Space extended upward; height; the perpendicular elevation of an object above its foundation, above the ground, or above a given level, or …
  1. 1.
    Space extended upward; height; the perpendicular elevation of an object above its foundation, above the ground, or above a given level, or of one object above another; as, the altitude of a mountain, or of a bird above the top of a tree.
  2. 2.
    The elevation of a point, or star, or other celestial object, above the horizon, measured by the arc of a vertical circle intercepted between such point and the horizon. It is either true or apparent; true when measured from the rational or real horizon, apparent when from the sensible or apparent horizon.(Astron.)
  3. 3.
    The perpendicular distance from the base of a figure to the summit, or to the side parallel to the base; as, the altitude of a triangle, pyramid, parallelogram, frustum, etc.(Geom.)
  4. 4.
    Height of degree; highest point or degree.
    “He is [proud] even to the altitude of his virtue.” Shak.
  5. 5.
    Height of rank or excellence; superiority.
  6. 6.
    Elevation of spirits; heroics; haughty airs.[Colloq.]
    “The man of law began to get into his altitude.” Sir W. Scott.
Phrases & compounds
Meridian altitude — an arc of the meridian intercepted between the south point on the horizon and any point on the meridian. See Meridian, 3.