From Abracadabra to Zombies
In a nutshell: A mentalist is someone who does shows where he seems to be psychic.
A mentalist is an entertainer who pretends to have ESP or to be able to move things by his thoughts (psychokinesis). Mentalists pretend to read minds and to see into the future or to suspend an object in mid-air using only thought to hold it there. You might say that mentalists are honest psychics. (Mentalist and magician Jamy Ian Swiss calls himself the honest liar.)