The Collaborative International Dictionary of English v.0.48:

Catchy \Catch"y\, a.
   1. Apt or tending to catch the fancy or attention; catching;
      taking; as, catchy music.
      [Webster 1913 Suppl.]

   2. Tending to catch or insnare; entangling; -- usually used
      fig.; as, a catchy question.
      [Webster 1913 Suppl.]

   3. Consisting of, or occuring in, disconnected parts or
      snatches; changeable; as, a catchy wind.
      [Webster 1913 Suppl.]

            It [the fox's scent] is . . . flighty or catchy, if
            variable.                             --Encyc. of
                                                  Sport.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

catchy
    adj 1: having concealed difficulty; "a catchy question"; "a
           tricky recipe to follow" [syn: catchy, tricky]
    2: likely to attract attention; "a catchy title for a movie"
       [syn: attention-getting, catchy]

Moby Thesaurus II by Grady Ward, 1.0:

114 Moby Thesaurus words for "catchy":
   achingly sweet, agreeable, agreeable-sounding, appealing, ariose,
   arioso, beguiling, broken, canorous, cantabile, capricious,
   careening, choppy, deceiving, deceptive, delusive, delusory,
   desultory, deviative, disconnected, discontinuous, dubious, dulcet,
   eccentric, erratic, euphonic, euphonious, euphonous, fallacious,
   false, fine-toned, fishy, fitful, flickering, fluctuating, golden,
   golden-tongued, golden-voiced, guttering, hallucinatory, halting,
   herky-jerky, heteroclite, honeyed, illusive, illusory,
   immethodical, inconstant, intermittent, intermitting, irregular,
   jerky, lurching, melic, mellifluent, mellifluous, mellisonant,
   mellow, melodic, melodious, misleading, music-flowing, music-like,
   musical, nonuniform, on-again-off-again, patchy, pleasant,
   pleasant-sounding, questionable, rambling, rich, rough, scrappy,
   silver-toned, silver-tongued, silver-voiced, silvery, singable,
   snatchy, songful, songlike, sonorous, spasmatic, spasmic,
   spasmodic, spastic, sporadic, spotty, staggering, sweet,
   sweet-flowing, sweet-sounding, trickish, tricksy, tricky, tunable,
   tuneful, uncertain, unequal, uneven, unmethodical, unmetrical,
   unregular, unrhythmical, unsettled, unsteady, unsystematic,
   variable, veering, wandering, wavering, wobbling, wobbly