The Collaborative International Dictionary of English v.0.48:

Synthetic \Syn*thet"ic\, Synthetical \Syn*thet"ic*al\, a. [Gr.
   ?: cf. F. synth['e]tique.]
   1. Of or pertaining to synthesis; consisting in synthesis or
      composition; as, the synthetic method of reasoning, as
      opposed to analytical.
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            Philosophers hasten too much from the analytic to
            the synthetic method; that is, they draw general
            conclusions from too small a number of particular
            observations and experiments.         --Bolingbroke.
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   2. (Chem.) Artificial. Cf. Synthesis, 2.
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   3. (Zool.) Comprising within itself structural or other
      characters which are usually found only in two or more
      diverse groups; -- said of species, genera, and higher
      groups. See the Note under Comprehensive, 3.
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   Synthetic language, or Synthetical language, an
      inflectional language, or one characterized by grammatical
      endings; -- opposed to analytic language. --R. Morris.
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