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]