I do not thisnk your dictionary definition is adequate. Belief, as we use the word in casual everyday speech, usually means a reasonale inference from evidence:
"I believeI can pass my Algebra test tomorrow."
In common parlance, it also means trust:
"I told my husband on our wedding day I really believed in him."
THeologically, Faith is not accepting something with little evidence, with dubious evidence, or against evidence: that is called the sin of credulity.
Philosophically, belief is accepting the knowledge of a knower, e.g. Person #1 knows from direct experience,strong evidence or dispositive proof; Person #2 believes Person #1 because he has evidence of another sort: evidence that Person #1 is honest and knowledgeable.
So your dictionary definiton only covers a small portion of the semantic field indicated by the words "faith" and "belief."
Given the fact that there are many religions, none of which believing in any other; how can any thinking human claim that their religion is IT?