A [German] chess term. Roughly meaning, a situation where any move would put the player (who makes that move) to some serious disadvantage. Since we can’t pass in chess, it usually implies losing the game or conceding a winning one to a draw.
There is no zugzwang in scrabble, not really—since we can always pass if we want to here. Nevertheless, I stumbled upon some close equivalent to it a couple of days ago.