The Collaborative International Dictionary of English v.0.48:

Prance \Prance\ (pr[.a]ns), v. i. [imp. & p. p. Pranced; p.
   pr. & vb. n. Prancing.] [OE. prauncen; probably akin to
   prank, v. t. See Prank.]
   1. To spring or bound, as a horse in high mettle.
      [1913 Webster]

            Now rule thy prancing steed.          --Gay.
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   2. To ride on a prancing horse; to ride in an ostentatious
      manner.
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            The insulting tyrant prancing o'er the field.
                                                  --Addison.
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   3. To walk or strut about in a pompous, showy manner, or with
      warlike parade. --Swift.
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WordNet (r) 3.0 (2006):

prance
    n 1: a proud stiff pompous gait [syn: strut, prance,
         swagger]
    v 1: to walk with a lofty proud gait, often in an attempt to
         impress others; "He struts around like a rooster in a hen
         house" [syn: tittup, swagger, ruffle, prance,
         strut, sashay, cock]
    2: spring forward on the hind legs; "The young horse was
       prancing in the meadow"
    3: cause (a horse) to bound spring forward
    4: ride a horse such that it springs and bounds forward