Noun

(en noun)

The absolute height of a location, usually measured from sea level.

* {{quote-magazine, date=2013-06-07, author=David Simpson

, volume=188, issue=26, page=36, magazine=(The Guardian Weekly) , title= Fantasy of navigation , passage=Like most human activities, ballooning has sponsored heroes and hucksters and a good deal in between. For every dedicated scientist patiently recording atmospheric pressure and wind speed while shivering at high altitudes , there is a carnival barker with a bevy of pretty girls willing to dangle from a basket or parachute down to earth.}}

A vertical distance.

(geometry) The distance measured perpendicularly from a figure's vertex to the opposite side of the vertex.

(astronomy) The angular distance of a heavenly body above our Earth's horizon.

Height of rank or excellence; superiority.

(Jonathan Swift)

(dated, in the plural) Elevation of spirits; heroics; haughty airs.

* Sir Walter Scott

The man of law began to get into his altitudes .

(Richardson)

Highest point or degree.

* Shakespeare

He is [proud] even to the altitude of his virtue.

Noun

(en noun)

(astronomy) The point in the sky vertically above a given position or observer; the point in the celestial sphere opposite the nadir.

* 1638 Herbert, Sir Thomas Some years travels into divers parts of Asia and Afrique

The 12 day wee had the wind high and large ?o that in two dayes ?aile we made the Sunne our Zenith or verticall point...

* 1671–1693 : Rev. Thomas Jolly, private notebook ; printed in:

* 1895 , Henry Fishwick (editor), The Note Book of the Rev. Thomas Jolly: A.D. 1671–1693. Extracts from the Church Books of Altham and Wymondhouses, 1649–1725. And an Account of the Jolly Family of Standish, Gorton, and Altham , page 44

In this 10th m. appeared that prodigious Comett the tayl whereof was like the blade of a double edged sword, and reached almost from the horizon to the zenith .

(astronomy) The highest point in the sky reached by a celestial body.

* 1719-

...in the middle of the day, when the sun was in the zenith , the violence of the heat was too great to stir out...

* 1920 , , The Understanding Heart , Chapter II:

As far to the west as Monica could see, her world was a sea of fog, , the fog gradually took on a bluish tinge.

Highest point or state; peak.

* Shakespeare

I find my zenith doth depend upon / A most auspicious star.

* Macaulay

It was during those civil troubles this aspiring family reached the zenith .

* {{quote-book

, page=173 , year=1900 , author=William Beckford , title=The History of the Caliph Vathek citation , passage="There for a while I enjoyed myself in the zenith of glory and pleasure."}}