1. [n]  any natural satellite of a planet; "Jupiter has sixteen moons"
2. [n]  the natural satellite of the Earth; "the average distance to the moon is 384,400 kilometers"; "men first stepped on the moon in 1969"
3. [n]  any object resembling a moon; "he made a moon lamp that he used as a night light"; "the clock had a moon that showed various phases"
4. [n]  the light of the moon; "moonlight is the smuggler's enemy"; "the moon was bright enough to read by"
5. [n]  the period between successive new moons (29.531 days)
6. [v]  expose one's buttocks to; "moon the audience"
7. [v]  be idle in a listless or dreamy way
8. [v]  have dreamlike musings or fantasies while awake; "She looked out the window, daydreaming"

Moon
The universe is not so vast when a child can hold a piece of it in his or her hand. In these shaped board books, both Sun and Moon are delightful characters who explain in very simple terms what they do for us on earth. Illustrations. 12 panels.

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1. \Moon\, n. [OE. mone, AS. m[=o]na; akin to D. maan, OS. &
   OHG. m[=a]no, G. mond, Icel. m[=a]ni, Dan. maane, Sw.
   m[*a]ne, Goth. m[=e]na, Lith. men?, L. mensis month, Gr. ?
   moon, ? month, Skr. m[=a]s moon, month; prob. from a root
   meaning to measure (cf. Skr. m[=a] to measure), from its
   serving to measure the time. [root]271. Cf. {Mete} to
   measure, {Menses}, {Monday}, {Month}.]
   1. 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}.
            The crescent moon, the diadem of night. --Cowper.
   2. A secondary planet, or satellite, revolving about any
      member of the solar system; as, the moons of Jupiter or
      Saturn.
   3. The time occupied by the moon in making one revolution in
      her orbit; a month. --Shak.
   4. (Fort.) A crescentlike outwork. See {Half-moon}.
   {Moon blindness}.
      (a) (Far.) A kind of ophthalmia liable to recur at
          intervals of three or four weeks.
      (b) (Med.) Hemeralopia.
   {Moon dial}, a dial used to indicate time by moonlight.
   {Moon face}, a round face like a full moon.
   {Moon madness}, lunacy. [Poetic]
   {Moon month}, a lunar month.
   {Moon trefoil} (Bot.), a shrubby species of medic ({Medicago
      arborea}). See {Medic}.
   {Moon year}, a lunar year, consisting of lunar months, being
      sometimes twelve and sometimes thirteen.
   

2. \Moon\, v. t. [imp. & p. p. {Mooned}; p. pr. & vb. n.
   {Mooning}.]
   To expose to the rays of the moon.
         If they have it to be exceeding white indeed, they
         seethe it yet once more, after it hath been thus sunned
         and mooned.                              --Holland.
   

3. \Moon\, v. i.
   To act if moonstruck; to wander or gaze about in an
   abstracted manner.
         Elsley was mooning down the river by himself. --C.
                                                  Kingsley.
   

heb. yareah, from its paleness (Ezra 6:15), and lebanah, the "white" (Cant. 6:10; Isa. 24:23), was appointed by the Creator to be with the sun "for signs, and for seasons, and for days, and years" (Gen. 1:14-16). A lunation was among the Jews the period of a month, and several of their festivals were held on the day of the new moon. It is frequently referred to along with the sun (Josh. 10:12; Ps. 72:5, 7, 17; 89:36, 37; Eccl. 12:2; Isa. 24:23, etc.), and also by itself (Ps. 8:3; 121:6).

The great brilliance of the moon in Eastern countries led to its being early an object of idolatrous worship (Deut. 4:19; 17:3; Job 31:26), a form of idolatry against which the Jews were warned (Deut. 4:19; 17:3). They, however, fell into this idolatry, and offered incense (2 Kings 23:5; Jer. 8:2), and also cakes of honey, to the moon (Jer. 7:18; 44:17-19, 25).