from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Astronomy A point on the celestial sphere directly below the observer, diametrically opposite the zenith.
- n. The lowest point: the nadir of their fortunes.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The point of the celestial sphere, directly opposite the zenith; inferior pole of the horizon; point of the celestial sphere directly under the place where we stand.
- n. The lowest point; time of greatest depression.
- n. The axis of a projected conical shadow; the direction of the force of gravity at a location; down.
- n. An empty box added beneath a full one in a beehive to give the colony more room to expand or store honey.
- v. To extend (a beehive) by adding an empty box at the base.
from the GNU version of the Collaborative International Dictionary of English
- n. 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.
- n. The lowest point; the time of greatest depression.
from The Century Dictionary and Cyclopedia
- n. That point of the heavens which is vertically below any station upon the earth.
- n. Hence The lowest point; the point of extreme depression.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the point below the observer that is directly opposite the zenith on the imaginary sphere against which celestial bodies appear to be projected
- n. an extreme state of adversity; the lowest point of anything
Middle English, from Medieval Latin, from Arabic naẓīr (as-samt), opposite (the zenith), from naẓara, to see, watch; see nṭr in Semitic roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Medieval Latin nadir, from Arabic نَظِيرُ السَّمْت (naẓīru as-samt), composed of السَمْتُ (as-samt, "the zenith") and نَظِير (naẓīr, "counterpart, corresponding to"). (Wiktionary)