The Collaborative International Dictionary of English v.0.48:

ingratiating \ingratiating\ adj.
   1. capable of winning favor; as, with open arms and an
      ingratiating smile.
      [WordNet 1.5]

   2. calculated to please or gain favor; as, an unctuous,
      ingratiating manner.

   Syn: ingratiatory.
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

Ingratiate \In*gra"ti*ate\, v. t. [imp. & p. p. Ingratiated;
   p. pr. & vb. n. Ingratiating.] [Pref. in- in + L. gratia.
   See Grace.]
   [1913 Webster]
   1. To introduce or commend to the favor of another; to bring
      into favor; to insinuate; -- used reflexively, and
      followed by with before the person whose favor is sought.
      [1913 Webster]

            Lysimachus . . . ingratiated himself both with
            Philip and his pupil.                 --Budgell.
      [1913 Webster]

   2. To recommend; to render easy or agreeable; -- followed by
      to. [Obs.] --Dr. J. Scott.
      [1913 Webster]

            What difficulty would it [the love of Christ] not
            ingratiate to us?                     --Hammond.
      [1913 Webster]

WordNet (r) 3.0 (2006):

ingratiating
    adj 1: capable of winning favor; "with open arms and an
           ingratiating smile"
    2: calculated to please or gain favor; "a smooth ingratiating
       manner" [syn: ingratiating, insinuating, ingratiatory]

Moby Thesaurus II by Grady Ward, 1.0:

62 Moby Thesaurus words for "ingratiating":
   abject, adulatory, apple-polishing, backscratching, beggarly,
   bland, bootlicking, brown-nosing, buttery, cajoling, cowering,
   crawling, cringing, crouching, deferential, disarming, fair-spoken,
   fawning, fine-spoken, flattering, footlicking, fulsome, glib,
   groveling, hangdog, honey-mouthed, honey-tongued, insinuating,
   insinuative, mealymouthed, obeisant, obsequious, oily,
   oily-tongued, on bended knee, parasitic, prostrate, saccharine,
   servile, silken, silky, slimy, smarmy, smooth, smooth-spoken,
   smooth-tongued, smug, sniveling, soapy, soft-spoken, sponging,
   suave, suave-spoken, sugary, sycophantic, timeserving, toadeating,
   toadying, toadyish, truckling, unctuous, wheedling