any of the stars which apparently always retain the same position in respect to one another.
Origin of fixed star
First recorded in 1555–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
any of the stars in the Ptolemaic system, all of which were thought to be attached to an outer crystal sphere thus explaining their apparent lack of movement
an extremely distant star whose position appears to be almost stationary over a long period of time
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
A star or other celestial object so distant from Earth that its position in relation to other stars appears not to change over time. The fixed stars, which include virtually all visible objects beyond the solar system, form the background against which the motions of the Sun, planets, and other bodies of the solar system are measured, and they provide the reference for determining sidereal time. In actuality, no celestial object has a fixed position in relation to any other, and the movement of so-called fixed stars can be measured by precise observation over long periods of time. See more at proper motion.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.