The Collaborative International Dictionary of English v.0.48:

Commix \Com*mix"\, v. t. & i. [imp. & p. p. Commixed; p. pr. &
   vb. n. Commixing.] [Pref. com- + mix: cf. L. commixtus, p.
   p. of commiscere. See Mix.]
   To mix or mingle together; to blend.
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         The commixed impressions of all the colors do stir up
         and beget a sensation of white.          --Sir I.
                                                  Newton.
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         To commix
         With winds that sailors rail at.         --Shak.
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