1
a
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
mooned; mooning; moons
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.
: to spend time in idle reverie : behave abstractedly
fans mooning over movie stars
Cite this Entry
“Moon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/moon. Accessed 20 Mar. 2025.
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