astro-


a combining form with the meaning “pertaining to stars or celestial bodies, or to activities, as spaceflight, taking place outside the earth's atmosphere,” used in the formation of compound words: astronautics; astrophotography.
Compare cosmo-.

Origin of astro-

< Greek, combining form of ástron a star, constellation, akin to astḗr star; cf. aster, -aster2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for astro-

astro-

combining form

indicating a heavenly body, star, or star-shaped structureastrology; astrocyte
indicating outer spaceastronautics

Word Origin for astro-

from Greek, from astron star
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

Science definitions for astro-

astro-

A prefix that means “star” (as in astrophysics), “celestial body” (as in astronomy), or “outer space” (as in astronaut).

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.