The Collaborative International Dictionary of English v.0.48:

Substantiate \Sub*stan"ti*ate\, v. t. [imp. & p. p.
   Substantiated; p. pr. & vb. n. Substantiating.]
   1. To make to exist; to make real. --Ayliffe.
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   2. To establish the existence or truth of by proof or
      competent evidence; to verify; as, to substantiate a
      charge or allegation; to substantiate a declaration.
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            Observation is, in turn, wanted to direct and
            substantiate the course of experiment. --Coleridge.
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