Sexual practice in which elderly folk perform surprise anal sex on others whilst they lean over a slot machine at a casino. Often this is facilitated by the receiver leaning on a walker.
"Herbert, let's head down to the Aisle of Capri Casino this Saturday for the buffet and some Jackpotting."
V. doing something that you should not... or using an implement for a purpose other then its intended purpose. Jackpotting always result in someone getting hurt and or something getting broken
"billy get off the roof of that car and stop jackpotting!"