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

While the storm has been pushed out to sea, powerful astronomical high tides are expected early Sunday along the New England coast, including Nantucket, the National Weather Service tweeted. CBS News, "Nor'easter high tides, gusty winds still pounding New England coast," 4 Mar. 2018 Be sure to visit Friends of the Cosmic Campground for a calendar of classes, star parties, and astronomical events. Megan Michelson, Outside Online, "These Are the Best Stargazing Spots in North America," 13 July 2018 Within seconds IceCube had alerted an armada of astronomical satellites, including the Fermi Gamma-ray Space Telescope. Dennis Overbye, New York Times, "It Came From a Black Hole, and Landed in Antarctica," 12 July 2018 In the excitement after Tanaka’s alert the astronomical community made up for lost time. Mark Bowen, Scientific American, "Neutrinos on Ice: Astronomers' Long Hunt for Source of Extragalactic "Ghost Particles" Pays Off," 12 July 2018 There have been some suggestion there is less interest and pride because of the pain of four years ago but the viewing figures have remained astronomical and the hunger for redemption is acute. Martin Rogers, USA TODAY, "'Brazil's Donald Trump': World Cup fate impacts far-right presidential candidate," 6 July 2018 The three Democrats also discussed issues of particular importance to Detroit voters at the forum, including the astronomical cost of auto insurance in the city, race relations and restoring mental health services after years of disinvestment. Kathleen Gray, Detroit Free Press, "Why Democratic candidates for Michigan governor want Detroit votes," 5 July 2018 Thus a heliocentric solar system might well have been a constant of astronomical thought from Babylon and classical Greece onwards. The Economist, "Empty sky, empty Earth?," 5 July 2018 The monumental rings of Stonehenge and similar sites were long thought unique to the British Isles, where Bronze Age priests and worshippers marked astronomical events, celebrated the passing of seasons, and buried their elites. Michael Price, Science | AAAS, "Rituals performed at this German ‘Stonehenge’ may link mysterious monument to its U.K. counterpart," 28 June 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

1 Sep 2018

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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).


alleviating pain or harshness

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