from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A great circle passing through the poles of the celestial sphere and intersecting the celestial equator at right angles.
from the GNU version of the Collaborative International Dictionary of English
- n. A small brass circle attached to the north pole of an artificial globe, and divided into twenty-four parts or hours. It is used to mark differences of time in working problems on the globe.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a great circle on the celestial sphere that passes through both celestial poles
Sorry, no etymologies found.