1

moon

play
noun \ˈmün\

Definition of moon

  1. 1a often capitalized :  the earth's natural satellite (see satellite 2a) that shines by the sun's reflected light, revolves about the earth from west to east in about 2912 days with reference to the sun or about 2713 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 theb :  one complete moon cycle consisting of four phases (see 1phase 1)c :  satellite 2; specifically :  a natural satellite of a planet the moons of Jupiter

  2. 2 :  an indefinite usually extended period of time a labor of many moons

  3. 3 :  moonlight keep out of the moon or it may turn your head — H. R. Haggard

  4. 4 :  something that resembles a moon: such asa :  a highly translucent (see translucent 1) spot on old porcelainb :  lunulec slang :  naked buttocks

  5. 5 :  something impossible or inaccessible reach for the moon

moonlike

play \-ˌlīk\ adjective

over the moon

  1. :  very pleased :  in high spirits

Examples of moon in a Sentence

  1. The telescope makes the craters on the surface of the moon incredibly clear.

  2. the orbit of the Moon around the Earth

  3. Europa and Io are both moons of Jupiter.

  4. a planet orbited by one moon

Recent Examples of moon from the Web

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.

Origin and Etymology of moon

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


2

moon

verb

Definition of moon

  1. transitive verb
  2. 1 :  to spend in idle reverie :  dream —used with away mooned the afternoon away

  3. 2 slang :  to expose one's naked buttocks to One of the boys mooned the crowd.

  4. intransitive verb
  5. :  to spend time in idle reverie :  behave abstractedly fans mooning over movie stars

Examples of moon in a Sentence

  1. One of the boys mooned the crowd.

  2. One of the boys mooned at the crowd.

Recent Examples of moon from the Web

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.

Origin and Etymology of moon

see 1moon


MOON Defined for English Language Learners

moon

play
noun

Definition of moon for English Language Learners

  • the moon : 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

Definition of moon for English Language Learners

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


MOON Defined for Kids

1

moon

play
noun \ˈmün\

Definition of moon for Students

  1. 1 :  the natural heavenly body that shines by reflecting light from the sun and revolves about the earth in about 2912 days

  2. 2 :  satellite 1


2

moon

play
verb

Definition of moon for Students

mooned

;

mooning


Medical Dictionary

moon

play
noun \ˈmün\

Medical Definition of moon

  1. :  lunula a



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