The Collaborative International Dictionary of English v.0.48:

Mesmerize \Mes"mer*ize\, v. t. [imp. & p. p. Mesmerized; p.
   pr. & vb. n. Mesmerizing.] [Also spelled mesmerise.]
   1. To bring into a state of mesmeric sleep; to hypnotize.
      [1913 Webster]

   2. To produce an intense fascination in; to spellbind.
      [PJC]

WordNet (r) 3.0 (2006):

mesmerized
    adj 1: having your attention fixated as though by a spell [syn:
           fascinated, hypnotized, hypnotised, mesmerized,
           mesmerised, spellbound, spell-bound, transfixed]

Moby Thesaurus II by Grady Ward, 1.0:

61 Moby Thesaurus words for "mesmerized":
   agape, aghast, agog, all agog, amazed, arrested, astonished,
   astounded, at gaze, awed, awestruck, becharmed, beguiled,
   bewildered, bewitched, breathless, captivated, caught, charm-bound,
   charmed, confounded, dumbfounded, dumbstruck, enchanted,
   enraptured, enravished, enthralled, entranced, fascinated, fixed,
   flabbergasted, gaping, gauping, gazing, gripped, held, hypnotized,
   in a trance, in awe, in awe of, lost in wonder, marveling,
   open-eyed, openmouthed, overwhelmed, popeyed, puzzled, rapt,
   rapt in wonder, spell-caught, spellbound, staggered, staring,
   stupefied, surprised, thunderstruck, under a charm, under a spell,
   wide-eyed, wonder-struck, wondering