The Collaborative International Dictionary of English v.0.48:

Persuasion \Per*sua"sion\, n. [L. persuasio; Cf. F. persuasion.]
   1. The act of persuading; the act of influencing the mind by
      arguments or reasons offered, or by anything that moves
      the mind or passions, or inclines the will to a
      determination.
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            For thou hast all the arts of fine persuasion.
                                                  --Otway.
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   2. The state of being persuaded or convinced; settled opinion
      or conviction, which has been induced.
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            If the general persuasion of all men does so account
            it.                                   --Hooker.
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            My firm persuasion is, at least sometimes,
            That Heaven will weigh man's virtues and his crimes
            With nice attention.                  --Cowper.
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   3. A creed or belief; a sect or party adhering to a certain
      creed or system of opinions; as, of the same persuasion;
      all persuasions are agreed.
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            Of whatever state or persuasion, religious or
            political.                            --Jefferson.
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   4. The power or quality of persuading; persuasiveness.
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            Is 't possible that my deserts to you
            Can lack persuasion?                  --Shak.
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   5. That which persuades; a persuasive. [R.]
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   Syn: See Conviction.
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WordNet (r) 3.0 (2006):

persuasion
    n 1: the act of persuading (or attempting to persuade);
         communication intended to induce belief or action [syn:
         persuasion, suasion] [ant: dissuasion]
    2: a personal belief or judgment that is not founded on proof or
       certainty; "my opinion differs from yours"; "I am not of your
       persuasion"; "what are your thoughts on Haiti?" [syn:
       opinion, sentiment, persuasion, view, thought]