A wrestling term for tripping up the heels.  It is derived from the Italian gamba (leg) and gambitare (set traps).  Ruy Lopez was the first to use it as a chess term for traps in his book in 1561 to describe the Damiano Gambit, 1.e4 e5 2.Nf3 f6 3.Nxe5.  Ruy Lopez learned the term from a visit to Rome, who used it as a slang term.  Greco introduced the term into England and France in 1623 (Joachimo’s Gambettos).

A gambit is a chess opening in which a piece (usually a pawn) is sacrificed in order to achieve an advantage.

There are three general methods in which a gambit can help a player's position. For a gambit to be sound it will typically have some degree of at least two of the following:

• Gain of Time: the player accepting the gambit must take time to procure the sacrificed material and possibly must use more time to reorganize his pieces after the material is taken.

• Generation of differential activity: Often a player accepting a gambit will decentralize his pieces or pawns and his poorly placed pieces will allow the gambiteer to place his own pieces and pawns on squares that may otherwise have been inaccessible. In addition, bishops and rooks can become more active simply because the loss of pawns often gives rise to open files and diagonals. Former world champion Mikhail Tal, one of the most extraordinary attacking players of the 20th century, once said that he had sacrificed a pawn just because "it was in his way."

• Generation of positional weaknesses: Finally, accepting a gambit may lead to a compromised pawn structure, holes or other positional deficiencies.