The Collaborative International Dictionary of English v.0.48:

Complicate \Com"pli*cate\, a. [L. complicatus, p. p. of
   complicare to fold together. See Complex.]
   1. Composed of two or more parts united; complex;
      complicated; involved.
      [1913 Webster]

            How poor, how rich, how abject, how august,
            How complicate, how wonderful is man! --Young.
      [1913 Webster]

   2. (Bot.) Folded together, or upon itself, with the fold
      running lengthwise.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Complicate \Com"pli*cate\, v. t. [imp. & p. p. Complicated; p.
   pr. & vb. n. Complicating.]
   To fold or twist together; to combine intricately; to make
   complex; to combine or associate so as to make intricate or
   difficult.
   [1913 Webster]

         Nor can his complicated sinews fail.     --Young.
   [1913 Webster]

         Avarice and luxury very often become one complicated
         principle of action.                     --Addison.
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         When the disease is complicated with other diseases.
                                                  --Arbuthnot.
   [1913 Webster]

WordNet (r) 3.0 (2006):

complicate
    v 1: make more complicated; "There was a new development that
         complicated the matter" [syn: complicate, perplex]
         [ant: simplify]
    2: make more complex, intricate, or richer; "refine a design or
       pattern" [syn: complicate, refine, rarify, elaborate]