Source : Webster's Revised Unabridged Dictionary (1913)

Festoon \Fes*toon"\, n. [F. feston (cf. Sp. feston, It.
   festone), prob. fr. L. festum festival. See {Feast}.]
   1. A garland or wreath hanging in a depending curve, used in
      decoration for festivals, etc.; anything arranged in this
      way.

   2. (Arch. & Sculp.) A carved ornament consisting of flowers,
      and leaves, intermixed or twisted together, wound with a
      ribbon, and hanging or depending in a natural curve. See
      Illust. of {Bucranium}.

Festoon \Fes*toon"\, v. t. [imp. & p. p. {Festooned}; p. pr. &
   vb. n. {Festooning}.]
   To form in festoons, or to adorn with festoons.

Source : WordNet®

festoon
     n 1: a curtain of fabric draped and bound at intervals to form
          graceful loops
     2: an embellishment consisting of a decorative representation
        of a string of flowers suspended between two points; used
        on pottery or in architectural work
     3: flower chains suspended in loops between points [syn: {festoonery}]
     v : decorate with strings of flowers; "The public buildings were
         festooned for the holiday"