The Collaborative International Dictionary of English v.0.48:

Scherzo \Scher"zo\, n. [It.] (Mus.)
   A playful, humorous movement, commonly in 3-4 measure, which
   often takes the place of the old minuet and trio in a sonata
   or a symphony.
   [1913 Webster]

WordNet (r) 3.0 (2006):

scherzo
    n 1: a fast movement (usually in triple time)

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "scherzo":
   adagietto, adagio, allegretto, allegro, andante, andantino,
   crescendo, decrescendo, diminuendo, forte, fortissimo, larghetto,
   larghissimo, largo, legato, marcando, pianissimo, piano, pizzicato,
   prestissimo, presto, rallentando, ritardando, ritenuto, scherzando,
   spiccato, staccato, stretto