The noun altitude refers to how high something rises: “The high altitude of the Himalayan mountain range slowed the progress of the hikers.”

Whether it refers to how high a plane is flying or to the height of a landform, the word altitude is used to describe an object’s elevation above a particular reference point. Altitude is typically measured from sea level, which is the average level of the sea’s surface. Something that is far above sea level — such as Mount Everest — is said to have a high altitude. Something closer to the ground — such as a plane approaching for landing — is said to have a low altitude.

Definitions of altitude
  1. noun
    elevation especially above sea level or above the earth's surface
    “the altitude gave her a headache”
    synonyms: height
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    height above ground
    (meteorology) altitude of the lowest layer of clouds
    maximum altitude at which a plane can fly (under specified conditions)
    absolute ceiling
    the maximum altitude at which an airplane can maintain horizontal flight
    combat ceiling, service ceiling
    altitude above which a plane cannot climb faster than a given rate
    type of:
    distance of something above a reference point (such as sea level)
  2. noun
    angular distance above the horizon (especially of a celestial object)
    synonyms: ALT, EL, elevation
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    type of:
    angular position
    relation by which any position with respect to any other position is established
  3. noun
    the perpendicular distance from the base of a geometric figure to the opposite vertex (or side if parallel)
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    type of:
    distance, length
    size of the gap between two places
Word Family

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