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Synonyms

astronomer

American  
[uh-stron-uh-mer] / əˈstrɒn ə mər /

noun

  1. an expert in astronomy; a scientific observer of the celestial bodies.


astronomer British  
/ əˈstrɒnəmə /

noun

  1. a scientist who studies astronomy

"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

Etymology

Origin of astronomer

First recorded in 1325–75; Middle English; see origin at astronomy, -er 1

Explanation

A scientist who studies the objects in the sky, including planets, galaxies, black holes, and stars, is called an astronomer. These days, the terms astronomer and astrophysicist are used interchangeably, to talk about any physicist who specializes in celestial bodies and the forces that affect them. Astronomers use telescopes and cameras to observe the stars and other objects in the sky, and they often use complicated math to make predictions and solve puzzles about their movements and locations. The Greek root, astronomia, literally means "star arrangement."

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The material, alongside Russian-language sources and collaboration with other academics, including the University of Tartu and former astronomer Dr John Butler, formed the basis of the exhibition at the planetarium.

From BBC • Apr. 20, 2026

If you’re an astronomer, it’s people confusing what you do with astrology.

From Salon • Apr. 14, 2026

"It's very exciting to see our simulations matched so closely by data from another galaxy," said Lars Hernquist, Mallinckrodt Professor of Astrophysics at Harvard and a CfA astronomer.

From Science Daily • Mar. 23, 2026

The calculation was created in the 1800s by a Belgian astronomer, and then a doctor in the U.S. renamed it the body mass index in the 1970s.

From MarketWatch • Mar. 18, 2026

The last scientist who worked in the Library was a mathematician, astronomer, physicist and the head of the Neoplatonic school of philosophy—an extraordinary range of accomplishments for any individual in any age.

From "Cosmos" by Carl Sagan