indicating a heavenly body, star, or star-shaped structure: astrology, astrocyte
WordReference Random House Learner's Dictionary of American English © 2026
-astro-, root.
WordReference Random House Unabridged Dictionary of American English © 2026- Aerospace, Astronomy-astro-, or -aster-, comes from Greek, where it has the meanings "star;
heavenly body;
outer space.'' These meanings are found in such words as: aster, asterisk, asteroid, astrology, astronomy, astronaut, astronautics, disaster.
astro-,
- Aerospace, Astronomya 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.
- Greek, combining form of ástron a star, constellation, akin to asté̄r star; compare aster, -aster2
Collins Concise English Dictionary © HarperCollins Publishers::
'astro-' also found in these entries (note: many are not synonyms or translations):
Astroturf
- aster
- astro-inertial guidance
- astroarchaeology
- astrobiology
- astrobleme
- astrochemistry
- astrocyte
- astrodome
- astrodynamics
- astrogate
- astrogeology
- astrograph
- astrolabe
- astrology
- astromancy
- astrometeorology
- astrometry
- astronaut
- astronautical
- astronavigation
- astronomy
- astrophotography
- astrophotometry
- astrophysics
- astrosphere
- celestial guidance
- cosmo-
- disaster