Con artist and Double-dealer

Con artist noun - A swindler who exploits the confidence of his victim.

Double-dealer and con artist are semantically related In some cases you can use "Double-dealer" instead a noun phrase "Con artist".

Double-dealer noun - One who betrays a trust or an allegiance.

Con artist and double-dealer are semantically related in cheat topic. Sometimes you can use "Con artist" instead a noun phrase "Double-dealer", if it concerns topics such as person who fools others, person who cheats another.