Fraudulent simply refers to anything that is deceptive or deceitful. When it comes to finding synonyms for this term, the list could be endless depending on the context. Some related words that could be used interchangeably with fraudulent include fake, phony, bogus, deceptive, dishonest, false, and spurious. Other synonyms that could apply to specific situations include counterfeit, forged, manipulative, duplicitous, and insincere. Ultimately, the choice of synonym would depend on the degree to which an act, statement, or situation is fraudulent, as well as the tone and style of communication used in conveying it.