[1] : The Collaborative International Dictionary of English v.0.48

unctuous \unc"tuous\ ?; 135, a. f. onctueux, ll. unctuosus,
   fr. l. unctus anointment, fr. ungere, unctum, to anoint. see
   unguent.
   1. of the nature or quality of an unguent or ointment; fatty;
      oily; greasy. "the unctuous cheese." --longfellow.
      1913 webster

   2. having a smooth, greasy feel, as certain minerals.
      1913 webster

   3. bland; suave; also, tender; fervid; as, an unctuous
      speech; sometimes, insincerely suave or fervid.
      1913 webster -- unc"tuously, adv. --
      unc"tuousness, n.
      1913 webster
see also:
unguent unc"tuously unc"tuousness 

[2] : WordNet (r) 2.0

unctuously
     adv : in an unctuous manner syn: smarmily, fulsomely
see also:
smarmily fulsomely 

Unctuously >> U Words
Unctuously, definition of term: Unctuously
unctuously_pag1.html