The Collaborative International Dictionary of English v.0.48:

Propitiatory \Pro*pi"ti*a*to*ry\, a. [L. propitiatorius: cf. F.
   propitiatoire.]
   Having the power to make propitious; pertaining to, or
   employed in, propitiation; expiatory; as, a propitiatory
   sacrifice. --Sharp.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Propitiatory \Pro*pi"ti*a*to*ry\, n. [L. propitiatorium.]
   (Jewish Antiq.)
   The mercy seat; -- so called because a symbol of the
   propitiated Jehovah. --Bp. Pearson.
   [1913 Webster]

WordNet (r) 3.0 (2006):

propitiatory
    adj 1: having power to atone for or offered by way of expiation
           or propitiation; "expiatory (or propitiatory) sacrifice"
           [syn: expiatory, expiative, propitiatory]
    2: intended to reconcile or appease; "sent flowers as a
       propitiatory gesture" [syn: propitiative, propitiatory]

Moby Thesaurus II by Grady Ward, 1.0:

70 Moby Thesaurus words for "propitiatory":
   Christlike, Christly, acquiescent, apologetic, appeasing, ascetic,
   atoning, celestial, cleansing, compensational, compensatory,
   compliant, conciliatory, deferential, divine, empyrean, expiatory,
   expurgatory, godlike, godly, heavenly, incarnate, incarnated,
   ingratiating, intercessional, intercessive, irenic, lustral,
   lustrational, lustrative, made flesh, mediative, mediatory,
   mollifying, obeisant, obliging, pacific, pacificatory, pacifying,
   penitential, piacular, placative, placatory, propitiative,
   purgative, purgatorial, purifying, reclamatory, recompensing,
   reconciliatory, redeeming, redemptive, redressing, reparative,
   reparatory, repentant, repenting, restitutional, restitutive,
   restitutory, righting, salvational, satisfactional, self-existent,
   soothing, squaring, superhuman, supernatural, tractable,
   transcendent