1 of 2


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
: one complete moon cycle consisting of four phases (see phase entry 1 sense 1)
: satellite sense 1
specifically : a natural satellite of a planet
the moons of Jupiter
: an indefinite usually extended period of time
a labor of many moons
: moonlight
keep out of the moon or it may turn your head H. R. Haggard
: something that resembles a moon: such as
: a highly translucent (see translucent sense 1) spot on old porcelain
: lunule
slang : naked buttocks
: something impossible or inaccessible
reach for the moon
moonlike adjective


2 of 2


mooned; mooning; moons

transitive verb

: to spend in idle reverie : dream
used with away
mooned the afternoon away
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
over the moon
: very pleased : in high spirits

Example Sentences

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. See More
Recent Examples on the Web
Finally, Artemis IV will fly to a space station near the moon. Max Zahn, ABC News, 15 Nov. 2022 The moon rocket, officially known as the Space Launch System (SLS), is currently set to launch in the early morning hours of Nov. 16, marking the beginning of the Artemis 1 lunar orbital mission. Jeffrey Kluger, Time, 11 Nov. 2022 If all goes well, NASA can move forward with the crewed Artemis II flight set for no earlier than May 2024, which will also orbit the moon. Richard Tribou, Orlando Sentinel, 11 Nov. 2022 Certain people are more compatible than others for various reasons explained through astrology, such as due to their element association or their moon or rising sign. Olivia Munson, USA TODAY, 10 Nov. 2022 These solar cells could aid space agencies like NASA in exploring alien worlds, such as the Jupiter moon Europa. Darren Orf, Popular Mechanics, 10 Nov. 2022 In June 2021, Juno got to within 600 miles of Ganymede, the largest moon in the Solar System, sending back some gorgeous images. Jamie Carter, Forbes, 10 Nov. 2022 The rocket’s inaugural takeoff is slated to send the Orion spacecraft to orbit the moon. Barbara Liston, Washington Post, 10 Nov. 2022 What is it called when the moon passes through the earth`s shadow? CNN, 10 Nov. 2022
An unruly passenger flying from Ireland to New York earlier this month got into trouble after allegedly creating multiple disturbances, going so far as to moon a flight attendant and throw an empty can at another passenger. Bailey Schulz, USA TODAY, 23 Jan. 2022 Bart, meanwhile, makes a statement by pulling down his leather and denim trousers to moon the audience. CNN, 4 Oct. 2021 Incredibly, #MeToo Marilyn, her body posed tilting slightly forward, will even be positioned to moon the museum. Christopher Knight Art Critic, Los Angeles Times, 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, 10 Apr. 2020 He’s even accused demonstrators of mooning security forces to provoke them. Washington Post, 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, 16 Oct. 2019 The paintings in the last two groups show their backsides, as if mooning viewers. David Pagel, Los Angeles Times, 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, 26 Aug. 2019 See More

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.

Word History


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

First Known Use


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


1836, in the meaning defined at transitive sense 1

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

Dictionary Entries Near moon

Cite this Entry

“Moon.” Dictionary, Merriam-Webster, Accessed 27 Nov. 2022.

Kids Definition

moon 1 of 2


: the earth's natural satellite that shines by reflecting light from the sun and revolves about the earth in about 29frac::1/2 days
: an unspecified and usually long period of time
took many moons to complete


2 of 2


: to spend time daydreaming

Medical Definition

More from Merriam-Webster on moon

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