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Definition of "moon" []

  • The natural satellite of Earth, visible by reflection of sunlight and having a slightly elliptical orbit, approximately 356,000 kilometers (221,600 miles) distant at perigee and 406,997 kilometers (252,950 miles) at apogee. Its mean diameter is 3,475 kilometers (2,160 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. (noun)
  • A natural satellite revolving around a planet. (noun)
  • The moon as it appears at a particular time in its cycle of phases: a gibbous moon. (noun)
  • A month, especially a lunar month. (noun)
  • A disk, globe, or crescent resembling the natural satellite of Earth. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "moon" in a sentence
  • "Moon Dreams - The Americans may still go to the moon before the Chinese, The Economist"
  • "NASA To Bomb The Moon (PHOTOS) * See photos below* NASA is launching a dramatic mission to bomb the moon."
  • "(Soundbite of song, "Moon and Moon") Ms. KHAN: (Singing) Calling moon and moon."