What is "synthetical language"

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.

   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.

2. (Chem.) Artificial. Cf. Synthesis, 2.

3. (Zo["o]l.) 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.

   Synthetic language, or Synthetical language, an inflectional language, or one characterized by grammatical endings; -- opposed to analytic language.
   --R. Morris.