from
The Collaborative International Dictionary of English v.0.48
Nadir \Na"dir\ (n[=a]"d[~e]r), n. [F., Sp., & It. nadir; all fr.
Ar. naz[imac]ru's samt nadir, prop., the point opposite the
zenith (as samt), in which naz[imac]r means alike,
corresponding to. Cf. {Azimuth}, {Zenith}.]
1. That point of the heavens, or lower hemisphere, directly
opposite the zenith; the inferior pole of the horizon; the
point of the celestial sphere directly under the place
where we stand.
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2. The lowest point; the time of greatest depression.
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The seventh century is the nadir of the human mind
in Europe. --Hallam.
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{Nadir of the sun} (Astron.), the axis of the conical shadow
projected by the earth. --Crabb.
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