The Collaborative International Dictionary of English v.0.48:

Proximate \Prox"i*mate\, a. [L. proximatus, p. p. of proximare
   to come near, to approach, fr. proximus the nearest, nest,
   superl. of propior nearer, and prope, adv., near.]
   Nearest; next immediately preceding or following. "Proximate
   ancestors." --J. S. Harford.
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         The proximate natural causes of it [the deluge]. --T.
                                                  Burnet.
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   Proximate analysis (Chem.), an analysis which determines
      the proximate principles of any substance, as contrasted
      with an ultimate analysis.

   Proximate cause.
   (a) A cause which immediately precedes and produces the
       effect, as distinguished from the remote, mediate, or
       predisposing cause. --I. Watts.
   (b) That which in ordinary natural sequence produces a
       specific result, no independent disturbing agencies
       intervening.

   Proximate principle (Physiol. Chem.), one of a class of
      bodies existing ready formed in animal and vegetable
      tissues, and separable by chemical analysis, as albumin,
      sugar, collagen, fat, etc.
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   Syn: Nearest; next; closest; immediate; direct.
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