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preclude vs. exclude

preclude
[pri-klood] / prɪˈklud /

verb (used with object)

precludes, present (3rd person singular) precluded, past participle, past precluding present participle

  1. to prevent the presence, existence, or occurrence of; make impossible.

    The insufficiency of the evidence precludes a conviction.
    Synonyms:
    eliminate, forestall

  2. to exclude or debar from something.

    His contract precludes a raise for him.
exclude
[ik-sklood] / ɪkˈsklud /

verb (used with object)

excludes, present (3rd person singular) excluded, past participle, past excluding present participle

  1. to shut or keep out; prevent the entrance of.

    Synonyms:
    preclude, omit, except, prohibit, bar
    Antonyms:
    include

  2. to shut out from consideration, privilege, etc..

    Employees and their relatives were excluded from participation in the contest.

  3. to expel and keep out; thrust out; eject.

    He was excluded from the club for infractions of the rules.
    Synonyms:
    reject