from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The time required for a complete rotation of the earth in reference to any star or to the vernal equinox at the meridian, equal to 23 hours, 56 minutes, 4.09 seconds in units of mean solar time.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. one day of sidereal time; the time in which Earth rotates once around its axis, relative to the point of the vernal equinox (about 23 hours, 56 minutes, 4 seconds)
- n. rotational period of Earth; the time in which Earth rotates around its axis 360 degrees
from the GNU version of the Collaborative International Dictionary of English
- n. the interval between two successive transits of the first point of Aries over the same meridian. The Sidereal day is 23 h. 56 m. 4.09 s. of mean solar time.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day
Sorry, no etymologies found.