This is the 4203rd most frequent Swedish word.
schack
Chess.
Here, 'schack' is used to refer to the game of chess.
Jag gillar att spela schack.
I like to play chess.
In this context, 'schack' describes a game situation where the opponent's king is under threat.
Han satte sin motståndare i schack.
He put his opponent in check.
The word 'schack' is being used to generally refer to the intellectual game.