Glossary of Chess

Laws of Chess: The rules of chess.
Lightning chess: A form of chess with an extremely short time limit, usually 1 or 2 minutes per player for the entire game.
Light squares: the 32 light-coloured squares on the chessboard, such as h1 and a8.
Light-square bishop: One of the two bishops moving on the light squares, situated on f1 or c8 in the initial position.
Line: 1. A sequence of moves, usually in the opening or in analyzing a position.; 2. An open path for a piece (queen, rook, or bishop) to move or control squares.
Liquidation: See simplification.
Long diagonal: One of the two diagonals with eight squares (a1–h8 or h1–a8).
Long-range piece: A bishop, rook, or queen.
Loss: A loss for one of the two players, which may occur due to that player being checkmated by the other player, resigning, exceeding the time control, or being forfeited by the tournament director. Chess being a zero-sum game, this results in a win for the other player, except in the very rare circumstance where the tournament director forfeits both players, for example for cheating or both players exceeding the time control (the latter does not normally result in a double forfeit today).
Lucena position: A well-known rook and pawn versus rook endgame position in which the player with the extra pawn can force a win.
Luft: (from the German for air) Space made for a castled king to give it a flight square to prevent a back rank mate. Usually luft is made by moving a pawn on the second rank in front of the king.