astrometric binary star

astrometric binary star

[¦as·trə¦me·trik ′bī‚ner·ē ′stär]
(astronomy)
A binary star that may be distinguished from a single star only from the variable proper motion of one of its components.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.