The Collaborative International Dictionary of English v.0.48:

Solitaire \Sol`i*taire"\, n. [F. See Solitary.]
   1. A person who lives in solitude; a recluse; a hermit.
      --Pope.
      [1913 Webster]

   2. A single diamond in a setting; also, sometimes, a precious
      stone of any kind set alone.
      [1913 Webster]

            Diamond solitaires blazing on his breast and wrists.
                                                  --Mrs. R. H.
                                                  Davis.
      [1913 Webster]

   3. A game which one person can play alone; -- applied to many
      games of cards, etc.; also, to a game played on a board
      with pegs or balls, in which the object is, beginning with
      all the places filled except one, to remove all but one of
      the pieces by "jumping," as in draughts.
      [1913 Webster]

   4. (Zool.)
      (a) A large extinct bird (Pezophaps solitaria) which
          formerly inhabited the islands of Mauritius and
          Rodrigeuz. It was larger and taller than the wild
          turkey. Its wings were too small for flight. Called
          also solitary.
      (b) Any species of American thrushlike birds of the genus
          Myadestes. They are noted their sweet songs and
          retiring habits. Called also fly-catching thrush. A
          West Indian species (Myadestes sibilans) is called
          the invisible bird.
          [1913 Webster]