Overview
A gambit (from Italian , the act of tripping someone with the leg to make them fall) is a chess opening in which a player sacrifices with the aim of achieving a subsequent advantage.
The word gambit is also sometimes used to describe similar tactics used by politicians or business people in a struggle with rivals in their respective fields, for example: "The early election was a risky gambit by Theresa May."
Terminology
The word "gambit" was originally applied to chess openings in 1561 by Spanish priest Ruy López de Segura, from an Italian expression dare il gambetto (to put a leg forward in order to trip someone). López studied this maneuver, and so the Italian word gained the Spanish form gambito that led to French gambit, which has influenced the English spelling of the word. The broader sense of "opening move meant to gain advantage" was first recorded in English in 1855.
Gambits are most commonly played by White. Some well-known examples of a gambit are the King's Gambit (1.e4 e5 2.f4) and Evans Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.b4). A gambit employed by Black may also be named a gambit, e.g. the Latvian Gambit (1.e4 e5 2.Nf3 f5), or Englund Gambit (1.d4 e5); but is sometimes named a "countergambit", e.g. the Albin Countergambit (1.d4 d5 2.c4 e5) and Greco Countergambit (the original name for the Latvian Gambit). Not all opening lines involving the sacrifice of material are named as gambits, for example the main line of the Two Knights Defense (1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Na5) in which Black sacrifices a pawn for active play is known as the "Knorre Variation", though it may be described as a "gambit". On the other hand, the Queen's Gambit (1.d4 d5 2.c4) is not a true gambit as Black cannot hold the pawn without incurring a disadvantage. As is often the case with chess openings, nomenclature is inconsistent.
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