Lexicon

This was defined by GM Nigel Short as "When you really have to go to the loo, so you make any move that won't ruin your position and run off."

If a quick move is made in a decisive stage of the game and therefore the whole game gets lost, it's said that the move had been a 'toilet move'. The less literal-minded will take it to mean a planless or bad waiting move.

If a player having the move intentionally touches a piece (one of his own or one of his opponent) he is bound to move it or capture the touched piece of his opponent. If you only want to correct the positions of your pieces on the chessboard, it's mandatory to warn the opponent before it by saying: "J'adoube" (French for: "I touch"), or "Adjust".

It is a tactic used to put the opponent in zugzwang (a position when it is a disadvantage to move). Triangulation is also called losing a tempo or losing a move.

Source: Wikipedia

Three pawns of the same colour on the same file.

The promotion of a pawn having reached the 8th rank to a piece other than a Queen. This type of promotion is sometimes also called as "minor promotion". The most common underpromotion, if happening, is the promotion to a Knight (often with check) to continue a combination. The other choices for it (to a Rook or Bishop) could be considered to avoid stalemate.
Underpromotion is directly connected to the characteristics of the given position. It is highly recommended to do a thorough analysis of the position to identify the important details helping you make the right decision.

A well-known underpromotion occurred in the game Korody-Balogh, Budapest 1933:
1.d4 d5 2.c4 e5 3.dxe5 d4 4.e3 Bb4+ 5.Bd2 dxe3! 6.Bxb4 exf2+ 7.Ke2 fxg1N+ 8.Rxg1 Bg4+ and White resigned.

A succession of moves played in a specific order. In the opening there are several variations and sub-variations available for a player to choose from. They are gathered together in opening books such as (for example) "Encyclopedia of chess openings".

A player who makes uncoordinated incoherent moves without any plan. It's said he or she only pushes wood around the chessboard.

It is widely known as a skewer (see its definition). It looks as if the attacking piece is able to X-ray through the enemy pieces.

This is a German term meaning "compulsion to move". It is a situation when any possible move will worsen this player's position.

A German chess term that means an "in-between" move that disrupts and changes the result of an otherwise logical sequence of moves.

Source: "Winning Chess Endings - Yasser Seirawan"

The term was introduced by Aaron Nimzovich in his book "My system" in the 1920s and it refers to actions taken by a player to anticipate and prevent the opponent's plans. It can be as simple as preventing a back rank mate by moving a pawn (usually h3/ h6) in front of the King side castle. The moves used are called prophylactic moves. See also prophylactic

A piece of paper both players use to write all details and moves of the game. Each player has one. Recording the game includes:
1. Both players names
2. Tournament name
3. Time and place
4. All moves for both sides
5. The final result
6. Both signatures
It is used in case of disputes to review the game up to that point, as well as to archive the game.

Chess-wise it is a specific position with a particular solution a chess lover can solve in order to get better.

In chess space means “control of squares”. A player has “space advantage” if it controls a greater number of squares. The opposite is also true: a player with a "cramped position" controls very few squares.

The threefold repetition rule (also known as repetition of position) states that a player can claim a draw if the same position occurs three times, or will occur after their next move, with the same player to move. The repeated positions do not need to occur in succession. The idea behind the rule is that if the position occurs three times, no progress is being made.

Source: Wikipedia

(or development)
Getting the pieces out of their original position and preferably in or near the center of the chessboard.

Or centre - the four squares in the middle of the board: e4, e5, d4, d5

Source: Wikipedia