altitude

American  

[al-ti-tood, -tyood] / ˈæl tɪˌtud, -ˌtjud /

noun

• altitudes
  plural

1. the height of anything above a given planetary reference plane, especially above sea level on earth.

   Synonyms:

   elevation

2. extent or distance upward; height.

   Antonyms:

   depth

3. Astronomy. the angular distance of a heavenly body above the horizon.

4. Geometry.

   1. the perpendicular distance from the vertex of a figure to the side opposite the vertex.

   2. the line through the vertex of a figure perpendicular to the base.

5. Usually altitudes. a high place or region.

   mountain altitudes.

6. high or important position, rank, etc.

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altitude British  

/ ˈæltɪˌtjuːd /

noun

1. the vertical height of an object above some chosen level, esp above sea level; elevation

2. geometry the perpendicular distance from the vertex to the base of a geometrical figure or solid

3. Also called: elevation.  astronomy nautical the angular distance of a celestial body from the horizon measured along the vertical circle passing through the body Compare azimuth

4. surveying the angle of elevation of a point above the horizontal plane of the observer

5. (often plural) a high place or region

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altitude Scientific  

/ ăl′tĭ-to̅o̅d′ /

1. The height of an object or structure above a reference level, usually above sea level or the Earth's surface.

2. Astronomy The position of a celestial object above an observer's horizon, measured in degrees along a line between the horizon (0°) and the zenith (90°). Unlike declination and celestial latitude —the corresponding points in other celestial coordinate systems—the altitude of star or other celestial object is dependent on an observer's geographic location and changes steadily as the sky passes overhead due to the rotation of the Earth.

3. Astronomy See more at altazimuth coordinate system

4. Mathematics The perpendicular distance from the base of a geometric figure, such as a triangle, to the opposite vertex, side, or surface.

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Synonym Usage

See height.

Other Word Forms

Derived Forms

• altitudinal
  adjective
• altitudinous
  adjective

Inflected Forms

Nouns

• altitudes
  plural

Etymology

Origin of altitude

First recorded in 1350–1400; Middle English, from Latin altitūdō; see origin at alti-, -tude

Explanation

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.

Example Sentences

See Examples For:

altitude altitudes

And did that impairment contribute to the aircraft's sudden loss of altitude?

From BBC ● Aug. 15, 2026

With increasing altitude and inventiveness and shrinking landing space.

From Salon ● Aug. 11, 2026

Pay particular attention to access to healthcare, as well as the things that matter most to you — language, proximity to other U.S. expats, climate, altitude, or being near the beach.

From MarketWatch ● Aug. 11, 2026

Seen against that history, her arguments no longer seem to descend from the altitude of solitary thought.

From The Wall Street Journal ● Aug. 7, 2026

Instead of repelling herself to a safe altitude, Holly crumpled onto the troll’s back, becoming instantly entangled in the ropy fur.

From "Artemis Fowl" by Eoin Colfer

Also used was a newer, more sophisticated system known as Terminal High Altitude Area Defense, or THAAD, which has a longer range and higher intercept altitudes than the older Patriot.

From BBC ● Jul. 27, 2026

Prized for their payloads, long ranges and ability to fly at high altitudes, B-52s have played a role in many U.S. conflicts, including the war with Iran.

From Los Angeles Times ● Jun. 19, 2026

Following months of flight testing, the X-59 team reviewed its progress in late May and is now preparing for a new phase that will push the aircraft to greater altitudes and higher speeds.

From Science Daily ● Jun. 1, 2026

Israeli military aircraft including drones generally fly at higher altitudes than commercial planes, he said, while such aircraft also show up on commercial planes' radars.

From Barron's ● Apr. 11, 2026

A third advantage of the Fertile Crescent’s Mediterranean zone is that it provides a wide range of altitudes and topographies within a short distance.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

Related Words

• distance
• elevation
• peak