The Collaborative International Dictionary of English v.0.48:

Preclude \Pre*clude"\, v. t. [imp. & p. p. Precluded; p. pr. &
   vb. n. Precluding.] [L. praecludere, praeclusum; prae
   before + claudere to shut. See Close, v.]
   1. To put a barrier before; hence, to shut out; to hinder; to
      stop; to impede.
      [1913 Webster]

            The valves preclude the blood from entering the
            veins.                                --E. Darwin.
      [1913 Webster]

   2. To shut out by anticipative action; to prevent or hinder
      by necessary consequence or implication; to deter action
      of, access to, employment of, etc.; to render ineffectual;
      to obviate by anticipation.
      [1913 Webster]

            This much will obviate and preclude the objections.
                                                  --Bentley.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

21 Moby Thesaurus words for "precluding":
   aside from, bar, barring, beside, besides, ex, except, except for,
   excepting, excluding, exclusive of, leaving out, let alone,
   omitting, outside of, save, save and except, saving, than, unless,
   without