What is the definition of fraud and what is the test for fraud?

As was explained in Wells v. Zenz (1927) 83 Cal.App. 137, 140, 256 P. 484, "Fraud is a generic term which embraces all the multifarious means which human ingenuity can devise and are resorted to by one individual to get an advantage over another. No definite and invariable rule can be laid down as a general proposition defining fraud, and it includes all surprise, trick, cunning, dissembling, and unfair way by which another is deceived...."