The Collaborative International Dictionary of English v.0.48:

Hedonist \Hed"on*ist\, n.
   One who believes in hedonism.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hedonist
    n 1: someone motivated by desires for sensual pleasures [syn:
         hedonist, pagan, pleasure seeker]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "hedonist":
   Cyrenaic, Heliogabalus, Sardanapalus, bon vivant, carpet knight,
   debauchee, epicure, epicurean, gourmand, gourmet, libertine,
   man-about-town, pleasure-seeker, rake, sensualist, sensuist, swine,
   sybarite, voluptuary