astronomy

American  

[uh-stron-uh-mee] / əˈstrɒn ə mi /

noun

1. the science that deals with the material universe beyond the earth's atmosphere.

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astronomy British  

/ əˈstrɒnəmɪ /

noun

1. the scientific study of the individual celestial bodies (excluding the earth) and of the universe as a whole. Its various branches include astrometry, astrodynamics, cosmology, and astrophysics

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astronomy Scientific  

/ ə-strŏn′ə-mē /

1. The scientific study of the universe and the objects in it, including stars, planets, nebulae, and galaxies. Astronomy deals with the position, size, motion, composition, energy, and evolution of celestial objects. Astronomers analyze not only visible light but also radio waves, x-rays, and other ranges of radiation that come from sources outside the Earth's atmosphere.

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astronomy Cultural  

1. The science that deals with the universe beyond the Earth. It describes the nature, position, and motion of the stars, planets, and other objects in the skies, and their relation to the Earth.

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Etymology

Origin of astronomy

First recorded in 1175–1225; Middle English astronomie, from Anglo-French, from Latin astronomia, from Greek; equivalent to astro- + -nomy

Compare meaning

How does astronomy compare to similar and commonly confused words? Explore the most common comparisons:

• astronomy vs. astrology

Example Sentences

"It'll be exciting, you know, in a slightly scary way, when they go behind the moon," Derek Buzasi, a professor of astronomy and astrophysics at the University of Chicago, told AFP.

From Barron's • Apr. 5, 2026

While religion provides answers, astronomy offers another way to search for them, grounding me like a kind of cosmic anchor.

From The Wall Street Journal • Mar. 31, 2026

The New Crescent Society is a British grassroots astronomy network founded in 2016, which seeks to unite British Muslims by following a sighting of the moon in the UK.

From BBC • Mar. 20, 2026

Wilson Observatory to satisfy his lifelong interest in astronomy.

From Los Angeles Times • Feb. 17, 2026

During the peak of ancient astronomy, Greek astronomical tables regularly employed zero; its symbol was the lowercase omicron, o, which looks very much like our modern-day zero, though it’s probably a coincidence.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Related Words

• astrophysics