The Collaborative International Dictionary of English v.0.48:

Self-righteous \Self`-right"eous\, a.
   Righteous in one's own esteem; pharisaic.
   [1913 Webster]

WordNet (r) 3.0 (2006):

self-righteous
    adj 1: excessively or hypocritically pious; "a sickening
           sanctimonious smile" [syn: holier-than-thou,
           pietistic, pietistical, pharisaic, pharisaical,
           sanctimonious, self-righteous]

Moby Thesaurus II by Grady Ward, 1.0:

27 Moby Thesaurus words for "self-righteous":
   Tartuffian, Tartuffish, affected, canting, complacent, false,
   goody, goody-goody, holier-than-thou, hypocritical, insincere,
   mealy-mouthed, mealymouthed, pecksniffian, pharisaic, pharisaical,
   pi, pietistic, pious, priggish, sanctified, sanctimonious,
   self-satisfied, smug, sniveling, superior, unctuous