In magic, magician's palm is a method for hiding a playing card in a seemingly-empty hand, in which the card is placed lengthwise against the palm and retained in the hand. The thumb sticking out as if "hitchhiking" is a "tell" or sign that a card is being palmed.The Classic Palm (Using a Coin), p. 190.Erdnase System of Palming, pp. 48-53.
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