cardsharp
A person who cheats at cards. Abreviated from cardsharper. Not someone who is good at cards, but someone who cheats. (Probably derived from the act of cheating by secretly scratching or marking cards during play with a sharp, hidden instrument.)
Idiots say "card shark."
cardsharp
A stage magician or illusionist who specializes in card tricks.
The master cardsharp was able to make the random card change color, value, and suite before the bewildered audience.