The Collaborative International Dictionary of English v.0.48:

Pantheistic \Pan`the*is"tic\, Pantheistical \Pan`the*is"tic*al\,
   a.
   Of or pertaining to pantheism; founded in, or leading to,
   pantheism. -- Pan`the*is"tic*al*ly, adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pantheistic
    adj 1: of or relating to pantheism [syn: pantheist,
           pantheistic]

Moby Thesaurus II by Grady Ward, 1.0:

93 Moby Thesaurus words for "pantheistic":
   Albigensian, Arian, Catharist, Cyrenaic, Donatist, Ebionitist,
   Eleatic, Epicurean, Erastian, Gnostic, Jansenist, Jansenistic,
   Jovinianist, Jovinianistic, Lollard, Manichaean, Megarian,
   Monophysite, Monophysitic, Montanist, Montanistic, Pelagian,
   Sabellian, Stoic, Waldensian, Wyclifite, animist, animistic,
   anthropomorphic, anthropotheistic, antinomian, apocryphal,
   atomistic, cosmotheistic, deistic, ditheistic, eclectic,
   emanationist, empirical, erroneous, eudaemonistic, existential,
   fallacious, hedonic, hedonist, hedonistic, heretical, heterodox,
   humanist, humanistic, hylotheist, hylotheistic, idealistic,
   instrumentalist, materialistic, mechanistic, metaphysical,
   monistic, monotheistic, naturalistic, nominalist, nonorthodox,
   panlogistical, pantheist, physicomorphic, polytheistic, positivist,
   positivistic, pragmatic, pragmatist, rationalistic, realist,
   realistic, religious, scholastic, sensationalistic, syncretistic,
   theistic, transcendentalist, transcendentalistic, tritheistic,
   unaccepted, unapproved, unauthentic, unauthoritative, uncanonical,
   unorthodox, unscriptural, unsound, utilitarian, vitalistic,
   voluntarist, voluntaristic