Each of these chess terms appears in my books or articles. When a chess term or one of its forms (such as its plural) is part of a definition, it is in italics.

center - the four squares touching the middle of the chessboard. These squares are called d4, d5, e4, and e5.

chessman - any piece or pawn.

chessmen - plural of chessman.

control - a chessman controls a square if it is legal for the chessman to move there, to capture the enemy chessman that's there, or to protect its own side's chessman that's there.

diagonal - a straight line of squares that touch each other only at the corners. If there are no other chessmen on a diagonal, a queen or bishop at one end of that diagonal can go to the other end of that diagonal in one move.

discovered check - a discovery where your unblocked piece is now checking your opponent's king.

discovery - when one of your chessmen that isn't controlling a square, moves away from where it blocked one of your pieces from controlling that square.

draw - a game that ends with no one winning or losing.

file - a straight line of eight squares that goes up and down the chessboard. Every square on a file begins with the same letter. If there are no other chessmen on a file, a major piece at one end of that file can go to the other end of that file in one move.

fork - when one of your chessmen moves to where it could safely capture at least two of your opponent's chessmen.

half-open file - a file where one player no longer has a pawn, but the other player still has at least one pawn. This file is open only for the player that doesn't have a pawn on it.

hole - a square on your third or fourth rank that none of your pawns can control anymore.

Example: moving White's b-pawn from b2 to b4 would create holes at a3 and a4, because the b-pawn was White's only pawn that could control those two squares.

kingside - the e- through h-files.

lose at least a pawn - have one of your pawns captured for free, or make a trade that gains the opponent one or more points altogether.

Example: trading a rook for the opponent's knight would lose you two points.

Example: trading your pawn for the opponent's pawn would not gain or lose.

major piece - a queen or rook.

minor piece - a bishop or knight.

open file - a file that no longer has any pawns on it. If there are no other pieces on an open file, a major piece at one end of that file can go to the other end of that file in one move.

passed pawn - a pawn that can reach promotion unless one of your opponent's pieces can stop it. This is where your opponent doesn't have pawns that can do the job.

pawn island - a group of pawns of a given player that are on adjacent files.

Example: at the start of a chess game, each player has one pawn island.

Example: the opening sequence 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 dxc6 would give Black two pawn islands.

pawn majority - a pawn island that outnumbers the opponent's pawns in that sector of the board and is separated from all other pawns by at least one open file.

Example: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 dxc6 5. d4 cxd4 6. Qxd4 Qxd4 7. Nxd4 would give White a four-to-three pawn majority on the kingside, and Black a four-to-three pawn majority on the queenside.

pawn promotion - when your pawn reaches the other side of the board, you get to replace it with a queen, rook, bishop, or knight. You should choose the queen almost all the time, since that piece is worth nine points. You are allowed to promote to a queen even if your original queen is still on the board.

piece - any king, queen, rook, bishop, or knight. A pawn isn't called a piece.

promoted piece - the piece that a pawn gets replaced with when it reaches the other side of the board. Since there's a choice, we can call it a promoted piece.

promotion - same as pawn promotion.

promotion square - this is where a pawn will end up if it reaches the other side of the board.

queening square - what most people say when they really mean promotion square. This is because pawns are almost always promoted to queens.

queenside - the a- through d-files.

rank - a straight line of eight squares that goes across the chessboard. Every square on a rank ends with the same number. If there are no other chessmen on a rank, a major piece at one end of that rank can go to the other end of that rank in one move.

sacrifice - lose at least a pawn on purpose, knowing that later in the game you will be ahead in points or checkmate your opponent. Be careful before you sacrifice!

shade - whether a given square is "light" or "dark." Traditionally, the word "color" is used, but this sometimes makes unclear whether a square or one of the players is being referred to.

space - room to move pieces. To create space, you have to move some pawns.

stalemate - where the side whose turn it is, has no legal move or capture, and its king is not in check. Stalemate counts as a draw.

take - means the same as capture, as in "bishop takes pawn."

the exchange - a rook for a minor piece. Phrases using this term include "win the exchange" (capture a rook for a minor piece), "up the exchange" (ahead by a rook for a minor piece), and "down the exchange" (behind by a rook for a minor piece).

win at least a pawn - capture a pawn for free, or make a trade that gains you one or more points altogether.

Example: trading a bishop for the opponent's rook would gain you two points.

Example: trading your pawn for the opponent's pawn would not gain or lose.