from The American Heritage® Dictionary of the English Language, 4th Edition
- n. See binary star.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Two stars which form a stellar system, such that they orbit the point of equilibrium of their gravitational fields; a binary star.
- n. Two stars that appear to be one when seen with the naked eye, either because they orbit one another (binary stars) or happen to be in the same line of sight even though they are separated by a great distance (optical binaries).
from the GNU version of the Collaborative International Dictionary of English
- adj. two stars so near to each other as to be seen separate only by means of a telescope. Such stars may be only optically near to each other, or may be physically connected so that they revolve round their common center of gravity, and in the latter case are called also binary stars.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a system of two stars that revolve around each other under their mutual gravitation
Sorry, no etymologies found.