al·ti·tude (ăltĭ-td′, -tyd′)
a. The height of a thing above a reference level, especially above sea level or above the earth's surface. See Synonyms at elevation.
b. Great height or elevation: has trouble breathing at altitude.
c. often altitudes A high location or area.
2. Astronomy The angular distance above the observer's horizon of a celestial object.
3. Mathematics The perpendicular distance from the base of a geometric figure to the opposite vertex, parallel side, or parallel surface.
[Middle English, from Latin altitūdō, from altus, high; see al-2 in the Appendix of Indo-European roots.]
al′ti·tudi·nal (-tdn-əl, -tyd-) adj.
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