The Collaborative International Dictionary of English v.0.48:

Spellbound \Spell"bound`\, a.
   Bound by, or as by, a spell.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Spellbind \Spell"bind`\, v. t. [imp. & p. p. Spellbound; p.
   pr. & vb. n. Spellbinding.]
   To bind or hold by, or as if by, a spell or charm; to
   entrance or fascinate, esp. by eloquence of speech, as in a
   political campaign. -- Spell"bind`er, n.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

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