A form of verbal bullying on the rails of a poker table when you beat somebody while holding a worse starting hand.
To 'Shakalak' someone is one of the best feelings in poker.
Scenario: Player 1 gives Player 2 a badbeat with JJ vs KK
Player 1: BOOOOMSHAKALAKAKAK
Player 2: Hey man thats not cool
Player 1: You just got shakalak'ed son
Player 3: Wow did you see player 1 SHAKALAKING player 2