Source : Webster's Revised Unabridged Dictionary (1913)

Placate \Pla"cate\, v. t. [imp. & p. p. {Placated}; p. pr. & vb.
   n. {Placating}.] [L. placatus, p. p. of placare to placate,
   akin to placere to please. See {Please}.]
   To appease; to pacify; to concilate. ``Therefore is he always
   propitiated and placated.'' --Cudworth.

Placate \Plac"ate\, n.
   Same as {Placard}, 4 & 5.

Source : WordNet®

placate
     v : cause to be more favorably inclined; gain the good will of;
         "She managed to mollify the angry customer" [syn: {pacify},
          {lenify}, {conciliate}, {assuage}, {appease}, {mollify},
          {gentle}, {gruntle}]