Source : Webster's Revised Unabridged Dictionary (1913)

Crescent \Cres"cent\, v. t.
   1. To form into a crescent, or something resembling a
      crescent. [R.] --Anna Seward.

   2. To adorn with crescents.

Crescent \Cres"cent\ (kr[e^]s"sent), a.
   1. Shaped like a crescent.

            Astarte, queen of heaven, with crescent horns.
                                                  --Milton.

   2. Increasing; growing.

            O, I see the crescent promise of my spirit hath not
            set.                                  --Tennyson.

Crescent \Cres"cent\ (kr[e^]s"sent), n. [OE. cressent,
   cressaunt, crescent (in sense 1), OF. creissant increasing,
   F. croissant, p. pr. of cro[^i]tre, OF. creistre, fr. L.
   crescere to increase, v. incho.; akin to creare to create.
   See {Create}, and cf. {Accrue}, {Increase}, {Crescendo}.]
   1. The increasing moon; the moon in her first quarter, or
      when defined by a concave and a convex edge; also, applied
      improperly to the old or decreasing moon in a like state.

   2. Anything having the shape of a crescent or new moon.

   3. A representation of the increasing moon, often used as an
      emblem or badge; as:
      (a) A symbol of Artemis, or Diana.
      (b) The ancient symbol of Byzantium or Constantinople.
          Hence:
      (c) The emblem of the Turkish Empire, adopted after the
          taking of Constantinople.

                The cross of our faith is replanted, The pale,
                dying crescent is daunted.        --Campbell.

   4. Any one of three orders of knighthood; the first
      instituted by Charles I., king of Naples and Sicily, in
      1268; the second by Ren['e] of Anjou, in 1448; and the
      third by the Sultan Selim III., in 1801, to be conferred
      upon foreigners to whom Turkey might be indebted for
      valuable services. --Brande & C.

   5. (Her.) The emblem of the increasing moon with horns
      directed upward, when used in a coat of arms; -- often
      used as a mark of cadency to distinguish a second son and
      his descendants.

Source : WordNet®

crescent
     adj : resembling the new moon in shape [syn: {crescent(a)}, {crescent-shaped},
            {semilunar}, {lunate}]

crescent
     n : any shape resembling the curved shape of the moon in its
         first or last quarters