astronomer

noun

as·​tron·​o·​mer ə-ˈsträ-nə-mər 

: a person who is skilled in astronomy or who makes observations of celestial phenomena

Examples of astronomer in a Sentence

Recent Examples on the Web

Only a fraction of all stars can have their planets detected, but every star can have their percentage of heavy elements (what astronomers call metallicity) measured. —Big Think, 17 Apr. 2026

But after further observations of its orbit, astronomers were able to rule out a risk of Apophis crashing into Earth for at least a century, according to NASA. —Eric Lagatta, USA Today, 16 Apr. 2026

Magnitude is the value used by astronomers to measure the brightness of objects in the night sky, the lower the number, the brighter the object! —Anthony Wood, Space.com, 16 Apr. 2026

Another group of astronomers caught sight of the asteroid again, later that same year, at an observatory in Australia. —Emily Mae Czachor, CBS News, 15 Apr. 2026

Word History

Etymology

Middle English, "one versed in astronomy or astrology," from astronomie astronomy + -er -er entry 2

Note: Alternatively, Oxford English Dictionary, third edition, and Middle English Dictionary see the English word as derived from Medieval and Late Latin astronomus "astronomer" (borrowed from Greek astronómos) plus the agent suffix -er.

First Known Use

14th century, in the meaning defined above

Rhymes for astronomer

• ionomer
• monomer