Most plaindealing is a phrase that refers to a person who is honest and straightforward, but there are several antonyms for this term. These antonyms include dishonest, deceitful, cunning, sly, insincere, manipulative, and fraudulent. Someone who is dishonest will lie and cheat to get what they want, while someone who is deceitful is tricky and uses deception to achieve their goals. Cunning individuals are often skilled at getting their way through sly means, and manipulative people will use any means necessary to achieve their objectives. Finally, fraudulent individuals use false claims and counterfeit means to deceive others. These antonyms are the polar opposite of most plaindealing, and they represent the qualities that people should avoid in life.