moon

noun
\ ˈmün How to pronounce moon (audio) \

Definition of moon

 (Entry 1 of 2)

1a often capitalized : the earth's natural satellite (see satellite sense 1a) that shines by the sun's reflected light, revolves about the earth from west to east in about 29¹/₂ days with reference to the sun or about 27¹/₃ days with reference to the stars, and has a diameter of 2160 miles (3475 kilometers), a mean distance from the earth of about 238,900 miles (384,400 kilometers), and a mass about one eightieth that of the earth usually used with the
b : one complete moon cycle consisting of four phases (see phase entry 1 sense 1)
c : satellite sense 1 specifically : a natural satellite of a planet the moons of Jupiter
2 : an indefinite usually extended period of time a labor of many moons
3 : moonlight keep out of the moon or it may turn your head— H. R. Haggard
4 : something that resembles a moon: such as
a : a highly translucent (see translucent sense 1) spot on old porcelain
b : lunule
c slang : naked buttocks
5 : something impossible or inaccessible reach for the moon
over the moon
: very pleased : in high spirits

moon

verb
mooned; mooning; moons

Definition of moon (Entry 2 of 2)

transitive verb

1 : to spend in idle reverie : dream used with away mooned the afternoon away
2 slang : to expose one's naked buttocks to One of the boys mooned the crowd.

intransitive verb

: to spend time in idle reverie : behave abstractedly fans mooning over movie stars

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Other Words from moon

Noun

moonlike \ ˈmün-​ˌlīk How to pronounce moon (audio) \ adjective

Synonyms for moon

Synonyms: Noun

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Examples of moon in a Sentence

Noun The telescope makes the craters on the surface of the moon incredibly clear. the orbit of the Moon around the Earth Europa and Io are both moons of Jupiter. a planet orbited by one moon Verb One of the boys mooned the crowd. One of the boys mooned at the crowd.
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Recent Examples on the Web: Noun The feat marked a key milestone for the private rocket company of billionaire tech mogul Elon Musk in its development of a resusable heavy-lift launch vehicle to eventually carry astronauts and large cargo payloads to the moon and Mars. Fox News, "SpaceX's Starship has successfully landed for the first time: what's next?," 6 May 2021 Stanciak used her painting of a forest with evergreen trees, stars and the moon as a template and the audience followed along doing their own art from home. Janice Neumann, chicagotribune.com, "Online painting lesson draws 75 people across 3 generations and raises $8K for Oak Lawn’s McDonald House," 4 May 2021 Before that decade was out, the watchmaker would be the first to reach the moon when Neil Armstrong and Buzz Aldrin wore the Speedmaster ST 105.012 onboard Apollo 11. Bryan Hood, Robb Report, "President Biden Wore His Trusted Omega Seamaster During His Pitch for the American Families Plan," 4 May 2021 At the start of next week don’t strain your eyes looking for the moon. Joe Mario Pedersen, orlandosentinel.com, "What’s in Orlando’s night sky during May? Meteor shower, supermoon and lunar eclipse," 4 May 2021 Other researchers have examined how dark matter might flow heat into neutron stars, planets, and the moon. Max G. Levy, Wired, "Where’s the Dark Matter? Look for Suspiciously Warm Planets," 3 May 2021 The last time that NASA astronauts splashed down in the nighttime was in 1968, when the three astronauts of Apollo 8, the first to orbit the moon, returned to Earth. New York Times, "SpaceX Makes First Nighttime Splashdown With Astronauts Since 1968," 2 May 2021 The former is an initiative that would return astronauts to the moon’s surface, and the latter is the sixth branch of the U.S. military designed specifically to operate outside of Earth’s atmosphere. Lawrence Richard, Washington Examiner, "Kamala Harris to lead Trump-revived National Space Council," 1 May 2021 On Saturday the moon will shift into Aries, and that energy will spike hard! Amy Solara, Travel + Leisure, "What This Week Will Bring for Your Zodiac Sign, According to an Astrologist: May 2–8, 2021," 30 Apr. 2021 Recent Examples on the Web: Verb Incredibly, #MeToo Marilyn, her body posed tilting slightly forward, will even be positioned to moon the museum. Christopher Knight Art Critic, Los Angeles Times, "Essential Arts: Why Palm Springs’ Monroe sculpture is a #MeToo Marilyn," 20 Mar. 2021 One of those includes Hayley’s brother Jack (Sam Claflin), haplessly mooning over his dream girl (Olivia Munn), an American war journalist who gets a few muttered zingers, but is otherwise stuck acting, well, dreamy. Amy Nicholson, New York Times, "‘Love Wedding Repeat’ Review: A Tumble Down the Aisle," 10 Apr. 2020 He’s even accused demonstrators of mooning security forces to provoke them. Washington Post, "Iraq’s military is spreading fake news about the protests — and Iraqis are laughing back," 18 Nov. 2019 Many on social media, however, did not find the mooning pumpkin man offensive and hit out at HOA’s policies. Alexandra Deabler, Fox News, "Homeowner censors Halloween decoration after HOA found the mooning pumpkin man offensive," 16 Oct. 2019 The paintings in the last two groups show their backsides, as if mooning viewers. David Pagel, Los Angeles Times, "In Dona Nelson’s magically messy paintings, the back is as revelatory as the front," 10 Oct. 2019 This episode, best remembered for the moment in which Julia accidentally moons a crowd (including the mayor of Atlanta), is a reminder that the series excelled at physical comedy in addition to sharp and rapid-fire dialogue. Kelly Lawler, USA TODAY, "The 5 best episodes of 'Designing Women,' in honor of its arrival on Hulu," 26 Aug. 2019 Someone apparently isn’t mooning over the huge, 10-by-30-foot mural that shows the bare buttocks of the Garden of Eden couple. USA TODAY, "Smokey Bear, tarantula trek, censoring Adam and Eve: News from around our 50 states," 9 Aug. 2019 Ultimately, one of the main goals of the program is to offset the cost of running the ISS—about $3 billion to $4 billion per year—as NASA shifts its spending from the aging station to moon and Mars missions. Stefanie Waldek, Condé Nast Traveler, "You Can Soon Vacation in Space for $35,000 Per Night," 10 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'moon.' 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 moon

Noun

before the 12th century, in the meaning defined at sense 1a

Verb

1836, in the meaning defined at transitive sense 1

History and Etymology for moon

Noun and Verb

Middle English mone, from Old English mōna; akin to Old High German māno moon, Latin mensis month, Greek mēn month, mēnē moon

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Time Traveler for moon

Time Traveler

The first known use of moon was before the 12th century

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Statistics for moon

Last Updated

9 May 2021

Cite this Entry

“Moon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/moon. Accessed 9 May. 2021.

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More Definitions for moon

moon

noun

English Language Learners Definition of moon

 (Entry 1 of 2)

: the large round object that circles the Earth and that shines at night by reflecting light from the sun
: a large round object like the moon that circles around a planet other than the Earth

moon

verb

English Language Learners Definition of moon (Entry 2 of 2)

informal : to bend over and show your bare buttocks to someone as a rude joke or insult

moon

noun
\ ˈmün How to pronounce moon (audio) \

Kids Definition of moon

 (Entry 1 of 2)

1 : the natural heavenly body that shines by reflecting light from the sun and revolves about the earth in about 29¹/₂ days

moon

verb
mooned; mooning

Kids Definition of moon (Entry 2 of 2)

moon

noun
\ ˈmün How to pronounce moon (audio) \

Medical Definition of moon

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More from Merriam-Webster on moon

Thesaurus: All synonyms and antonyms for moon

Nglish: Translation of moon for Spanish Speakers

Britannica English: Translation of moon for Arabic Speakers

Comments on moon

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