Jinx Switch is what became the name of a card sleight that was described in "The Jinx" #36 (September 1937) as part of the routine "Call Your Hand" by Annemann. A packet of cards is switched with a packet from the bottom of the deck (leaving the switched out packet on top of the deck).
Very similar to an old gamblers move where you switch the packet by placing the deck on top of the packet on the table (which leaves the switched out packet on the bottom of the deck). This was described in How Gamblers Win (1865).
Conjuring Credits' article on cards:jinx_switch