an important tactical mechanism which occurs when a moving piece leaves a line, uncovering a friendly piece behind it which in turn attacks an enemy piece on the same line
When one piece is moved, uncovering an attack by another piece. For example, if White's Bishop is between White's Queen and Black's King and the Bishop is moved to another square, the King is then in check from White's Queen (discovered check). (See also double attack.)
The creation of an attack from one piece caused by the moving away of another piece that was masking it. These are potent moves, as they may enable a piece to move away from a threat in safety, or enables two attacks to be launched simultaneously.
A player, by moving a piece, uncovers an attack on an opponent's piece.
An attack made by a queen, rook or bishop when another piece or pawn moves out of its way.
to attack by moving a piece or pawn out of the way of a line-piece such as rook, bishop or queen. 1.e4 discovers an attack on b5 and h5. There are examples in the Tactics section of the Canon.
In chess, a discovered attack is an attack revealed when one piece moves out of the way of another. The discovered check is a special case of this, where the unmasked attack is a check (conceivably, the piece moving away can also give check; in that case a double check results). Discovered attacks in general, and double checks in particular, can be extremely powerful, as the piece moved can make a threat independently of the piece it reveals.
