Astronomy is the science of stars, planets and everything beyond the earth. Study astronomy, an astronomy club, radio astronomy.
It is one of the oldest sciences and one of the few where amateurs still make real discoveries, particularly of comets and variable stars. Astrophysics is the branch concerned with how objects work rather than where they are. Note astrology, which is not a science and is constantly confused with this; and astronomical, which in ordinary speech simply means enormous, as in astronomical prices.
1nounastronomyThe science of stars, planets and space.
“He has taught astronomy for about thirty years.”
astronomy is a science.
Greek astronomia is astron, a star, plus nomos, a law — the law of the stars. Astrology is astron plus logos, the study of them, and the two words swapped meanings several times before settling.
Old French
astronomie
Middle English
astronomie
English, today
astronomy
From Middle English astronomie, astronemy, from Old French astronomie, equivalent to astro- + -nomy. Displaced native tungolcræft.
Etymology from Wiktionary, CC BY-SA