The Collaborative International Dictionary of English v.0.48:

Smile \Smile\, v. t.
   1. To express by a smile; as, to smile consent; to smile a
      welcome to visitors.
      [1913 Webster]

   2. To affect in a certain way with a smile. [R.]
      [1913 Webster]

            And sharply smile prevailing folly dead. --Young.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Smile \Smile\ (sm[imac]l), v. i. [imp. & p. p. Smiled
   (sm[imac]ld); p. pr. & vb. n. Smiling.] [OE. smilen; akin
   to Dan. smile, Sw. smila, MHG. smielen, smieren, L. mirari to
   wonder at, Skr. smi to smile; and probably to E. smicker.
   [root]173. Cf. Admire, Marvel, Smirk.]
   1. To express amusement, pleasure, moderate joy, or love and
      kindness, by the features of the face; to laugh silently.
      [1913 Webster]

            He doth nothing but frown. . . . He hears merry
            tales and smiles not.                 --Shak.
      [1913 Webster]

            She smiled to see the doughty hero slain. --Pope.
      [1913 Webster]

            When last I saw thy young blue eyes, they smiled.
                                                  --Byron.
      [1913 Webster]

   2. To express slight contempt by a look implying sarcasm or
      pity; to sneer.
      [1913 Webster]

            'T was what I said to Craggs and Child,
            Who praised my modesty, and smiled.   --Pope.
      [1913 Webster]

   3. To look gay and joyous; to have an appearance suited to
      excite joy; as, smiling spring; smiling plenty.
      [1913 Webster]

            The desert smiled,
            And paradise was opened in the wild.  --Pope.
      [1913 Webster]

   4. To be propitious or favorable; to favor; to countenance;
      -- often with on; as, to smile on one's labors.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Smile \Smile\, n. [CF. Dan. smiil, Sw. smil. See Smile, v. i.]
   1. The act of smiling; a peculiar change or brightening of
      the face, which expresses pleasure, moderate joy, mirth,
      approbation, or kindness; -- opposed to frown.
      [1913 Webster]

            Sweet intercourse
            Of looks and smiles: for smiles from reason flow.
                                                  --Milton.
      [1913 Webster]

   2. A somewhat similar expression of countenance, indicative
      of satisfaction combined with malevolent feelings, as
      contempt, scorn, etc; as, a scornful smile.
      [1913 Webster]

   3. Favor; countenance; propitiousness; as, the smiles of
      Providence. "The smile of heaven." --Shak.
      [1913 Webster]

   4. Gay or joyous appearance; as, the smiles of spring.
      [1913 Webster]

            The brightness of their [the flowers'] smile was
            gone.                                 --Bryant.
      [1913 Webster]

WordNet (r) 3.0 (2006):

smile
    n 1: a facial expression characterized by turning up the corners
         of the mouth; usually shows pleasure or amusement [syn:
         smile, smiling, grin, grinning]
    v 1: change one's facial expression by spreading the lips, often
         to signal pleasure
    2: express with a smile; "She smiled her thanks"

Moby Thesaurus II by Grady Ward, 1.0:

62 Moby Thesaurus words for "smile":
   accost, address, be in heaven, be pleased, beam, bob, bow,
   bright smile, broad grin, caper, caracole, chirp, chirrup,
   crack a smile, curtsy, dance, delight, die with delight,
   ear-to-ear grin, embrace, feel happy, frolic, gambol,
   gleaming smile, glow, glowing smile, go into raptures, greeting,
   grin, grinning, hail, hand-clasp, handshake, hello, how-do-you-do,
   hug, idiotic grin, joy, kiss, laugh, lilt, nod, purr,
   radiate cheer, romp, salutation, salute, sardonic grin, simper,
   sing, skip, smile brightly, smile of recognition, smiling, smirk,
   sparkle, stupid grin, take great satisfaction, toothful grin,
   tread on air, wave, whistle