A sacrifice (usually of a pawn) used to gain an early advantage of space and /or time in the opening.
2. Game score
The record of a game in some form of notation. In over-the-board tournaments, the gamescore is recorded on a score sheet.
3. Good bishop
A bishop which has high mobility, typically because the player's pawns are on squares of color opposite to that of the bishop.
The highest title a chess player can attain (besides World Champion). When used precisely, it is the title awarded by FIDE starting in 1950, but it can be used to describe someone of comparable ability. The term International Grandmaster or IGM would refer only to the FIDE title.
5. Grandmaster draw
A game in which the players quickly agree to a draw after making little or no effort to win. This may be a very boring game, e.g. 1.d4 d5 2.c4 c6 3.cxd5 cxd5 4.Nc3 Nf6 5.Nf3 Nc6 6.Bf4 Bf5 7.e3 e6 Draw Agreed, or a superficially exciting game played with a variation the players know leads to a draw, e.g. 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 dxc6 5.0-0 Bg4 6.h3 h5 7.c3 Qd3 8.hxg4 hxg4 9.Nxe5 Bd6 (a pseudo-sacrifice of Black's queen) 10.Nxd3 Bh2+ 11.Kh1 Bd6+ and Black draws by perpetual check. Although originally used to refer to such games between grandmasters, the term is now used colloquially to refer to any such game.
6. Greek gift sacrifice
Also known as the classical bishop sacrifice, it is a typical sacrifice of a bishop by White playing Bxh7+ or Black playing Bxh2+ against a castled king to initiate a mating attack.
7. Half-open file
A file on which only one player has no pawns.
Unprotected and exposed to capture. It is not the same as en prise since a piece en prise may be protected. To "hang a piece" is to lose it by failing to move or protect it.
10. Hanging pawns
Two friendly pawns abreast without friendly pawns on adjacent files. Hanging pawns can be either a strength (usually because they can advance) or a weakness (because they cannot be defended by pawns) depending on circumstances.
11. Harrwitz bishops
A player's light-squared and dark-squared bishops placed so that they occupy adjacent diagonals; named for the mid-19th century master Daniel Harrwitz. For example, White has Harrwitz bishops in the Danish Gambit after 1.e4 e5 2.d4 exd4 3.c3 dxc3 4.Bc4 cxb2 5.Bxb2. Harrwitz bishops can be a potent attacking force in the middlegame. Also called raking bishops.
12. Heavy piece
A queen or rook, also known as a major piece.
A square that a player does not, and cannot in future, control with a friendly pawn. The definition is somewhat subjective: the square must have some positional significance for the opponent to be considered a hole – squares on the first and second ranks are not holes. On the other hand a square is a hole even if it can be controlled in the future with a pawn that has made a capture. An example of the hole is the square e4 in the Stonewall Attack.
An opening system geared towards controlling the center with distant pieces as opposed to occupying it with pawns. See also Classical.