credulity - Dictionary definition and meaning for word credulity
credibility means belief on proved evidences and credulity means believing too easily
CRED means to believe so, credo, credible, credence, credit, credential, credulity, incredulous, creed, incredible all are associated with believe.
If you gave your friend a fake credit card, and if he/she think's it's real then he's a credulous person.
if money is credit in our account then we belive the bank