astronomy
noun
as·tron·o·my
ə-ˈsträ-nə-mē
plural astronomies
: the study of objects and matter outside the earth's atmosphere and of their physical and chemical properties
Did you know?
The Difference Between Astronomy and Astrology
Some may find it easy to confuse astronomy and astrology. At one time, these two words actually were synonymous (that is, astronomy once meant what astrology means today), but they have since moved apart from each other. In current use, astronomy is concerned with “the study of objects and matter outside the earth's atmosphere,” while astrology is the purported divination of how stars and planets influence our lives. Put bluntly, astronomy is a science, and astrology is not.
Cite this Entry
“Astronomy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/astronomy. Accessed 20 Aug. 2026.
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