The Collaborative International Dictionary of English v.0.48:

Felicitate \Fe*lic"i*tate\, a. [L. felicitatus, p. p. of
   felicitare to felicitate, fr. felix, -icis, happy. See
   felicity.]
   Made very happy. [Archaic]
   [1913 Webster]

         I am alone felicitate
         In your dear highness' love.             --Shak.
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The Collaborative International Dictionary of English v.0.48:

Felicitate \Fe*lic"i*tate\, v. t. [imp. & p. p. Felicitated;
   p. pr. & vb. n. felicitating.] [Cf. F. f['e]liciter.]
   1. To make very happy; to delight.
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            What a glorious entertainment and pleasure would
            fill and felicitate his spirit.       --I. Watts.
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   2. To express joy or pleasure to; to wish felicity to; to
      call or consider (one's self) happy; to congratulate.
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            Every true heart must felicitate itself that its lot
            is cast in this kingdom.              --W. Howitt.

   Syn: See Congratulate.
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WordNet (r) 3.0 (2006):

felicitate
    v 1: express congratulations [syn: congratulate, felicitate]