as·​tro·​nom·​i·​cal | \ ˌa-strə-ˈnä-mi-kəl How to pronounce astronomical (audio) \
variants: or less commonly astronomic \ ˌa-​strə-​ˈnä-​mik How to pronounce astronomic (audio) \

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 \ ˌa-​strə-​ˈnä-​mi-​k(ə-​)lē How to pronounce astronomically (audio) \ 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 The first day of astronomical autumn, or the fall equinox, will be Sept. 22 at 8:30 a.m. CDT. Leigh Morgan, al, "Summer solstice 2020: It’s the longest day of the year, sort of," 20 June 2020 That number, while still astronomical by historical standards, was a drop off from the 329,289 claims processed during the first week of June but topped the 302,712 claims the agency handled during the last week in May. Chase Difeliciantonio,, "Almost 1 in 6 Californian workers are unemployed," 19 June 2020 The summer solstice -- the start to summer according to the astronomical calendar -- is also the longest day in the Northern Hemisphere. Derek Van Dam, CNN, "Canada heat wave could lead to record temperatures as the southeastern US struggles to reach average summer temperatures," 18 June 2020 The astronomical start of summer is at 5:43 p.m. on June 20, the moment when the sun reaches its farthest northerly position in the sky, making that the longest day of the year. USA TODAY, "Silver Dollar City, ‘Thunder’ silenced, empty Vegas buffets: News from around our 50 states," 16 June 2020 SpaceX is working with the astronomical community to mitigate those concerns, testing dark coatings and now sunshades to come up with a solution. William Harwood, CBS News, "SpaceX launches another 60 Starlink internet satellites, pushes total to nearly 500," 4 June 2020 Across the country, police budgets are astronomical and police union power is enormous. Amna A. Akbar, The New York Review of Books, "How Defund and Disband Became the Demands," 2 June 2020 It’s the ultimate story of Black small-business owners persevering in spite of the astronomical challenges placed in front of them on the way to greatness. Shalwah Evans, Essence, "This Black Business Owner's Heartwarming Story Is A Lesson In Determination," 12 June 2020 Take it to a Lagrange point between the Earth and the moon, a likely spot for a future space platform, or down to the moon, and the costs become astronomical. Tim Fernholz, Quartz, "NASA will set a price on lunar ice. Why?," 11 June 2020

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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Time Traveler for astronomical

Time Traveler

The first known use of astronomical was in 1551

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Statistics for astronomical

Last Updated

30 Jun 2020

Cite this Entry

“Astronomical.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2020.

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More Definitions for astronomical


How to pronounce astronomical (audio)

English Language Learners Definition of astronomical

: of or relating to astronomy
: extremely large


as·​tro·​nom·​i·​cal | \ ˌa-strə-ˈnä-mi-kəl How to pronounce astronomical (audio) \
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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