moon

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. 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.
2. n. A natural satellite revolving around a planet.
3. n. The moon as it appears at a particular time in its cycle of phases: a gibbous moon.
4. n. A month, especially a lunar month.
5. n. A disk, globe, or crescent resembling the natural satellite of Earth.
6. n. Moonlight.
7. n. Something unreasonable or unattainable: They acted as if we were asking for the moon.
8. n. Slang The bared buttocks.
9. v. To wander about or pass time languidly and aimlessly.
10. v. To yearn or pine as if infatuated.
11. v. Slang To expose one's buttocks in public as a prank or disrespectful gesture.
12. v. Slang To expose one's buttocks to (others) as a prank or disrespectful gesture: "threatened to moon a passing . . . camera crew” ( Vanity Fair).

Century Dictionary and Cyclopedia

1. n. A heavenly body which revolves around the earth monthly, accompanying the earth as a satellite in its annual revolution, and shining by the sun's reflected light. Next to the sun, the moon is the most conspicuous and interesting of celestial objects. The rapidity of its motion, the variety of its phases, and especially the striking phenomena of eclipses, compelled the attention of the earliest observers; and the fact that lunar observations can be made available to determine the longitude has given the theory of the moon's motion the first rank in economic importance, while the mathematical problems involved have proved most interesting and fertile from the scientific point of view. Of all the heavenly bodies (meteors excepted) the moon is nearest to us. Its mean distance is a little more than sixty times the radius of the earth, or 238,800 miles. The dimensions of the moon as compared with those of the earth are far greater than those of any other satellite in proportion to its primary. Its diameter is 2,162 miles (about 0.273 of the earth's equatorial diameter), and its volume, or bulk, is 0.0204, or about one forty-ninth of that of the earth. Its mean density, however (about 3.4 times that of water), is only about three fifths of that of the earth, and its mass about one eightieth. The inclination of its orbit to the ecliptic is 5°8' 40“. It completes its revolution around the earth in an average period of 27d. 7h. 43m. 11.5s., which constitutes the sidereal month; the ordinary, or synodical, month, from new moon to new moon again, is a little more than two days longer — 29d. 12h. 44m. 2.7s. (See month.) The moon's orbital motion is subject to considerable inequalities, due to the disturbing action of the sun, and the investigation of these inequalities makes up the major part of the “lunar theory.” The moon revolves on its axis once in a sidereal month, thus always presenting nearly the same face to the earth — a circumstance which has led to the fallacy of a denial of its rotation. (See rotation.) Its disk appears to the naked eye diversified by dark and bright patches, giving rise to the “man in the moon” of popular fancy (see under man); but on examination with a powerful telescope these are lost sight of, and replaced by a crowd of interesting objects. such as mountains and valleys, craters and clefts, on a scale unknown upon the earth: the surface-structure seems to be mainly volcanic, resembling very closely in certain respects, and differing most markedly in others from, that which is characteristic of volcanic regions on the earth's surface. The moon has no clouds, shows no indications of an atmosphere or of the presence of water, and is believed to have a temperature which at its maximum does not rise above the melting-point of ice. See libration.
2. n. A satellite of any planet: as, the moons of Jupiter; Uranian moons.
3. n. The period of a synodical revolution of the moon round the earth; a month.
4. n. Something in the shape of a moon, especially of a half-moon or crescent. Specifically
5. n. In brickmaking, an implement of the nature of a slicebar, for slicing or loosening fires in the grates of brickkilns. It is somewhat longer than half the width of the kiln, and has a nearly circular blade perforated in the middle, which is shoved in on the top of the grate and under the fire, to clear out ashes and brighten up the fire.
6. n. The golden-crested wren, Regulus cristatus. Also moonie, muin. See cut under goldcrest.
7. n. The moon-daisy or moon-flower. Also moons
8. To adorn with a moon or moons; furnish with crescents or moon-shaped marks.
9. To expose to the rays of the moon.
10. To wander or gaze idly or moodily about, as if moonstruck.
11. n. An obsolete spelling of moan.
12. n. Moonlight.
13. In opposum-hunting, to locate (the hiding-place of the animal) by bringing the tree in which it is supposed to lurk into clear view between one's self and the moon.
14. To shave (skins) with a moon or moon-knife. See mooning, 1.

Wiktionary

1. n. The largest satellite of Earth.
2. n. Any natural satellite of a planet.
3. n. literary A month, particularly a lunar month.
4. v. transitive, colloquial To display one's buttocks to, typically as a jest, insult, or protest
5. v. intransitive, colloquial (usually followed by over or after) To fuss over something adoringly; to be infatuated with someone.
6. v. To spend time idly, absent-mindedly.

GNU Webster's 1913

1. n. The celestial orb which revolves round the earth; the satellite of the earth; a secondary planet, whose light, borrowed from the sun, is reflected to the earth, and serves to dispel the darkness of night. The diameter of the moon is 2,160 miles, its mean distance from the earth is 240,000 miles, and its mass is one eightieth that of the earth. See Lunar month, under month.
2. n. A secondary planet, or satellite, revolving about any member of the solar system.
3. n. The time occupied by the moon in making one revolution in her orbit; a month.
4. n. (Fort.) A crescentlike outwork. See Half-moon.
5. n. slang The deliberately exposed naked buttocks.
6. v. To expose to the rays of the moon.
7. v. To expose one's naked buttocks to (a person); -- a vulgar sign of contempt or disrespect, sometimes done as a prank.
8. v. To act if moonstruck; to wander or gaze about in an abstracted manner.

WordNet 3.0

1. v. have dreamlike musings or fantasies while awake
2. v. be idle in a listless or dreamy way
3. n. United States religious leader (born in Korea) who founded the Unification Church in 1954; was found guilty of conspiracy to evade taxes (born in 1920)
4. n. the period between successive new moons (29.531 days)
5. v. expose one's buttocks to
6. n. any object resembling a moon
7. n. any natural satellite of a planet
8. n. the natural satellite of the Earth
9. n. the light of the Moon