as·​tro·​nom·​i·​cal | \ ˌas-trə-ˈnä-mi-kəl \
variants: or less commonly astronomic \ -​mik \

Definition of astronomical

1 : of or relating to astronomy astronomical observations
2 : enormously or inconceivably large or great astronomical numbers an astronomical price

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Other Words from astronomical

astronomically \ -​mi-​k(ə-​)lē \ adverb

Examples of astronomical in a Sentence

The cost of the office building was astronomical. We got an astronomical telephone bill this month.

Recent Examples on the Web

In 2010, the military relocated our family from Illinois to San Diego, where the cost of living seemed astronomical. Sandy M. Fernandez, Woman's Day, "How Three Women Are Pioneering to End Hunger in the U.S.," 14 Nov. 2018 While the difficulties of building such an elevator are astronomical, the potential for financial benefits are equally large. David Grossman, Popular Mechanics, "Space Elevators Getting First Test in Space," 4 Sep. 2018 When a rural carrier's customer regularly travels outside the rural area, the cost to support that rural customer accessing T-Mobile's network through a roaming agreement can be astronomical. Jon Brodkin, Ars Technica, "T-Mobile/Sprint merger will bring higher prices, small carriers tell FCC," 30 Aug. 2018 But its margins are razor thin because its operational costs are astronomical. Nick Statt, The Verge, "Amazon and Walmart’s rivalry is reshaping how we’ll buy everything in the future," 3 Aug. 2018 The Dumplin' actress' astronomical professional success constantly plays second fiddle to her personal life—and what the public thinks is wrong with it. Christopher Rosa, Glamour, "Jennifer Aniston Says the Idea of Having Kids Is 'Frightening' to Her," 7 Dec. 2018 The summer solstice is an annual astronomical phenomenon that brings the longest day of the year in the northern hemisphere (and the shortest night). Tom Metcalfe /, NBC News, "What is the summer solstice?," 20 June 2018 Haro served as the head of the astronomy institute at the University of Mexico and created Mexico's National Institute of Astrophysics, Optics, and Electronics to expand the country's astronomical research. Madeline Buxton,, "Today's Google Doodle Celebrates Legendary Astronomer Guillermo Haro," 21 Mar. 2018 The astronomer was credited with discovering a new class of nebula that helped promote astronomical research in Mexico. Mackenzie Cummings-grady, Billboard, "Google Doodle Celebrates 105th Birthday of Famed Astronomer Guillermo Haro," 21 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'astronomical.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of astronomical

1551, in the meaning defined at sense 1

History and Etymology for astronomical

see astronomy

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Last Updated

20 Jan 2019

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Time Traveler for astronomical

The first known use of astronomical was in 1551

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English Language Learners Definition of astronomical

: of or relating to astronomy

: extremely large


as·​tro·​nom·​i·​cal | \ ˌa-strə-ˈnä-mi-kəl \
variants: or astronomic \ -​ik \

Kids Definition of astronomical

1 : of or relating to astronomy astronomical research
2 : extremely or unbelievably large The cost was astronomical.

Other Words from astronomical

astronomically adverb an astronomically large amount

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Comments on astronomical

What made you want to look up astronomical? Please tell us where you read or heard it (including the quote, if possible).


to gather or build up little by little

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