The Collaborative International Dictionary of English v.0.48:

Belief \Be*lief"\, n. [OE. bileafe, bileve; cf. AS. gele['a]fa.
   See Believe.]
   1. Assent to a proposition or affirmation, or the acceptance
      of a fact, opinion, or assertion as real or true, without
      immediate personal knowledge; reliance upon word or
      testimony; partial or full assurance without positive
      knowledge or absolute certainty; persuasion; conviction;
      confidence; as, belief of a witness; the belief of our
      senses.
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            Belief admits of all degrees, from the slightest
            suspicion to the fullest assurance.   --Reid.
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   2. (Theol.) A persuasion of the truths of religion; faith.
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            No man can attain [to] belief by the bare
            contemplation of heaven and earth.    --Hooker.
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   3. The thing believed; the object of belief.
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            Superstitious prophecies are not only the belief of
            fools, but the talk sometimes of wise men. --Bacon.
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   4. A tenet, or the body of tenets, held by the advocates of
      any class of views; doctrine; creed.
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            In the heat of persecution to which Christian belief
            was subject upon its first promulgation. --Hooker.
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   Ultimate belief, a first principle incapable of proof; an
      intuitive truth; an intuition. --Sir W. Hamilton.
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   Syn: Credence; trust; reliance; assurance; opinion.
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Moby Thesaurus II by Grady Ward, 1.0:

73 Moby Thesaurus words for "belief":
   a belief, acceptance, acquiescence, arrogance, article of faith,
   assent, assurance, assuredness, axiom, canon, certainty, certitude,
   cocksureness, concept, confidence, confidentness, conviction,
   courage, credence, credibility, credit, credo, creed, dependence,
   doctrine, dogma, eye, faith, feeling, fundamental, hubris, idea,
   intuition, judgement, law, maxim, mind, opinion, orthodoxy,
   overconfidence, oversureness, overweening, overweeningness,
   persuasion, poise, pomposity, positiveness, precept, pride,
   principle, principles, reliance, religion, religious belief,
   religious faith, security, self-assurance, self-confidence,
   self-importance, self-reliance, sentiment, settled belief,
   subjective certainty, sureness, surety, system of beliefs,
   teaching, tenet, theology, tradition, trust, trustworthiness,
   view