Definition of altitude in US English:


(also alt.)


  • 1The 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’
    • ‘During the trek she will be walking at altitudes of up to 4, 000m and will spend two days acclimatising.’
    • ‘The pilot said it was a rare day because the air was flowing in different directions between altitudes.’
    • ‘There are plenty of beautiful mountains and stunning views to be found at much lower altitudes.’
    • ‘I had been to the Himalayas before but I'd never experienced high altitudes.’
    • ‘Apparently, the altimeters built into some Casio watches can be modified to detonate bombs at certain altitudes.’
    • ‘The famous seven hills of Rome were healthy because mosquitoes, the vectors of malaria, only fly at low altitudes.’
    • ‘Air at very high altitude smells completely different to lower altitudes.’
    • ‘The rest of the flight is done at altitudes that those missiles cannot reach.’
    • ‘Flights will take off from the U.S. and will reach altitudes of more than 62 miles.’
    • ‘We had our fighter planes at several altitudes but met no enemy aircraft.’
    • ‘The expedition in March will see the duo facing altitudes of up to 14,000 ft and temperatures as low as minus five.’
    • ‘In its upper reaches, climbers are at heights equal to the cruising altitudes for passenger jets.’
    • ‘Therefore, the airplane may not be controllable at lower altitudes and airspeeds.’
    • ‘At high altitudes, the thin air makes it hard to breathe unless the cabin is pressurized.’
    • ‘From my experience, this airspeed holds true in a wide range of temperatures and altitudes.’
    • ‘There are also a large number of birds that are spotted at the higher altitudes so the climb is well worth the effort.’
    • ‘Eventually they reached for the skies and achieved dizzying altitudes.’
    • ‘From high altitudes they can locate missile sites and protect troops on the ground if called to do so.’
    • ‘Their goal is to fly to the highest altitudes that the sky and the human spirit can offer.’
    • ‘During the debrief, everyone claimed to have been at the prescribed altitudes and positions.’
    height, elevation, distance above the ground, distance above the sea
    View synonyms
    1. 1.1 Great height.
      ‘the mechanism can freeze at altitude’
      • ‘Kelly wants to develop the Astroliner, a winged rocket towed into the air by a 747 jet and released at altitude to soar on a suborbital trajectory under its own power.’
      • ‘The Superfort, its mission apparently completed, descended from altitude and the pilot decided to do a bit of joy riding.’
      • ‘If cabin depressurization occurs at altitude and goes above this value, passengers in shirt sleeves will die shortly.’
      • ‘The material soaks up water that freezes at altitude and can cause delamination that may not be readily visible.’
      • ‘Both nations have struggled in recent years while playing at altitude, where the thin air hands an advantage to those acclimatised to the conditions.’
      • ‘Most people don’t sleep well at altitude.’
      • ‘He spends long periods of time training at altitude in his home country.’
      • ‘This century's leap into aviation and space travel has brought with it a much deeper understanding of the human ability to function at altitude.’
    2. 1.2Astronomy The apparent height of a celestial object above the horizon, measured as an angle.
      • ‘Like other nautical instruments its primary function was to measure the altitude of the sun or a star above the horizon.’
      • ‘Also, on any given day the Sun circles the sky at the same apparent altitude.’
      • ‘Spacecraft orbiting Earth can be found in several different types of orbits based on their altitude and orientation.’
      • ‘A scale along the staff showed the altitude, or angle above the horizon, of the body.’
      • ‘If the object is below the horizon then the altitude is negative.’
    3. 1.3Geometry The length of the perpendicular line from a vertex to the opposite side of a figure.
      • ‘This is a good deal like having a theory that tells us that the area of a plane figure is one-half the base times the altitude, without telling us for what figures this holds.’
      • ‘Let y be the altitude of the triangular cross section of the wedge in Figure 6a cut by a plane at distance x from the base.’


Late Middle English: from Latin altitudo, from altus ‘high’.