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moon (mn)
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n.
1. often Moon The natural satellite of Earth, visible by reflection of sunlight and having a slightly elliptical orbit, approximately 363,100 kilometers (225,600 miles) distant at perigee and 405,700 kilometers (252,100 miles) at apogee. Its mean diameter is 3,475 kilometers (2,159 miles), its mass approximately one eightieth that of Earth, and its average period of revolution around Earth 29 days 12 hours 44 minutes calculated with respect to the sun.
2. A natural satellite revolving around a planet.
3. The moon as it appears at a particular time in its cycle of phases: a gibbous moon.
4. A month, especially a lunar month.
5. A disk, globe, or crescent resembling the natural satellite of Earth.
6. Moonlight.
7. Something unreasonable or unattainable: They acted as if we were asking for the moon.
8. Slang The bared buttocks.
v. mooned, moon·ing, moons
v.intr.
1. To wander about or pass time languidly and aimlessly.
2. To yearn or pine as if infatuated.
3. Slang To expose one's buttocks in public as a prank or disrespectful gesture.
v.tr.
Slang To expose one's buttocks to (others) as a prank or disrespectful gesture: "threatened to moon a passing ... camera crew" (Vanity Fair).
Idiom:
over the moon
In a state of great happiness.

[Middle English mone, from Old English mōna; see mē-2 in the Appendix of Indo-European roots.]
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moon
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moon
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moon
top: waxing crescent moon
center: full moon
bottom: third quarter moon

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2016 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Moon (mn), Sun Myung 1920–2012.
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Korean-born American religious leader and founder of the Unification Church (1954). He was found guilty in 1982 of conspiracy to evade taxes in the United States.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2016 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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