Zugzwang is the term, a German word, for the situation where any move loses, but if the player could “pass” it would be fine. There is no “pass” move in chess. You are simply required to make a move, any legal move at all. If you fail to move, you lose on time on the chess clock.
Zugzwang doesn’t just mean that you’re losing and every move is bad. It requires that the current situation is fine. Only the compulsion to move causes you to lose.
Zugzwang only really arises in the endgame. The concept of “the opposition” in King-and-Pawn endgames is a type of zugzwang. There is also a method of invading with your King into the enemy’s pawns that involves using zugzwang to force the enemy King away from its own pawns.
Occasionally there are situations in the middlegame where zugzwang comes into play. These are usually situations where the defender has gotten so tied up that they only have pawn moves left.
Related Chess Tactics
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