Triangulation (chess)

Triangulation is a tactic used in chess to put one's opponent in zugzwang (a position in which it is a disadvantage to move). Triangulation is also called losing a tempo or losing a move.

Triangulation occurs most commonly in endgames with only kings and pawns when one king can maneuver on three adjacent squares in the shape of a triangle and maintain the basic position while the opposing king only has two such squares. Thus, if one king triangulates by using three moves to return to the original square and the opposing king cannot do the same, he has lost a crucial tempo and reached the same position with the other player to move. Triangulation can occur in other endgames and even in some middlegames.^[1]