pre·clude 
(prĭ-kld)
(prĭ-kld)tr.v. pre·clud·ed, pre·clud·ing, pre·cludes
1. To make impossible, as by action taken in advance; prevent. See Synonyms at prevent.
2. To exclude or prevent (someone) from a given condition or activity: Modesty precludes me from accepting the honor.
[Latin praeclūdere : prae-, pre- + claudere, to close.]
pre·clusion (-klzhən) n.
pre·clusive (-klsĭv, -zĭv) adj.
pre·clusive·ly adv.