Stayman is a bidding convention in the card game contract bridge. It is used by a partnership to find a 4-4 or 5-3 trump fit in a major suit after making a one notrump (1NT) opening bid and it has been adapted for use after a 2NT opening, a 1NT overcall, and many other natural notrump bids.
Acol is the bridge bidding system that, according to The Official Encyclopedia of Bridge, is "standard in British tournament play and widely used in other parts of the world". It is a natural system using four-card majors and, most commonly, a weak no trump.
Polish Club is a bridge bidding system which was developed in Poland, where it is the most popular bidding system, and which is also used by players of other countries. It is a type of small club system.
A game try in the card game of bridge is a bid that shows interest in bidding a game and asks partner to help in making the decision.
The forcing notrump is a bidding convention in the card game of bridge.
The Jacoby transfer, or simply transfers, in the card game contract bridge, is a convention in Standard American bidding systems initiated by responder following partner's notrump opening bid that forces opener to rebid in the suit ranked just above that bid by responder. For example, a response in diamonds forces a rebid in hearts and a response in hearts forces a rebid in spades. Transfers are used to show a weak hand with a long major suit, and to ensure that opener declare the hand if the final contract is in the suit transferred to, preventing the opponents from seeing the cards of the stronger hand.
Zar Points (ZP) is a statistically derived method for evaluating contract bridge hands developed by Zar Petkov. The statistical research Petkov conducted in the areas of hand evaluation and bidding is useful to bridge players, regardless of their bidding or hand evaluation system. The research showed that the Milton Work point count method, even when adjusted for distribution, is not sufficiently accurate in evaluating all hands. As a result, players often make incorrect or sub-optimal bids. Zar Points are designed to take many additional factors into consideration by assigning points to each factor based on statistical weight. While most of these factors are already implicitly taken into account by experienced players, Zar Points provides a quantitative method that allows them to be incorporated into bidding.
Preempt is a bid in contract bridge whose primary objectives are (1) to thwart opponents' ability to bid to their best contract, with some safety, and (2) to fully describe one's hand to one's partner in a single bid. A preemptive bid is usually made by jumping, i.e. skipping one or more bidding levels. Since it deprives the opponents of the bidding space, it is expected that they will either find a wrong contract of their own, or fail to find any. A preemptive bid often has the aim of a sacrifice, where a partnership bids a contract knowing it cannot be made, but assumes that, the penalty will still be smaller than the value of opponents' bid and made contract.
Cappelletti is a bridge bidding convention for the card game contract bridge, primarily used to interfere over opponent's one notrump (1NT) opening. Usually attributed to Michael Cappelletti and his longtime partner Edwin Lewis, origin of the concept is also claimed by Fred Hamilton, John Pottage and Gerald Helms.
Landy, named after its inventor Alvin Landy is the first of several conventional defenses created to compete against an opponent's one notrump (1NT) opening. Landy is a 2♣ overcall of the opponents' 1NT opening to show at least four cards in each of the major suits; all other bids are natural. Requirements for the overcall vary from partnership to partnership: some require 5-5, some 5-4, and yet others only 4-4. The partner can take a preference to either major or make a non-forcing bid of a suit; 2NT is used as a forcing query.
Multi 2 diamonds, or simply Multi, is a contract bridge convention whereby the opening bid of 2♦ shows multiple types of hands, which always includes a weak-two bid in either major suit, while the additional meaning may be a strong balanced hand, or a 20-22 three suiter. The inherent ambiguity as to both suit and strength makes it a powerful and popular convention capable of seriously disrupting the opponents' bidding.
A reverse, in the card game contract bridge, is a bidding sequence designed to show additional strength without the need to make a jump bid; specifically two suits are bid in the reverse order to that expected by the basic bidding system. Precise methods and definitions vary with country, bidding system and partnership agreements.
Inverted minors refers to a treatment introduced by the Kaplan–Sheinwold (K–S) bidding system for the popular card game bridge. The original structure of Precision, another bidding system, also employed inverted minors over a 1♦ opening. However, the treatment is no longer restricted to users of these bidding systems. although partnerships that use a Short club system tend also to use the convention only after a 1♦ opener.
New Minor Forcing (NMF), is a contract bridge bidding convention used to find a 5-3 or 4-4 major suit fit after a specific sequence of bids in which opener has rebid one notrump. The convention is triggered by responder at his second turn by an artificial bid of two in an unbid minor; it requires that he hold five cards in the major he has previously bid and an unlimited hand ranging in value from at least game invitational strength to that sufficient to have interest in slam; he may also hold four cards in the other major. Accordingly, there are six bidding sequences in which the New Minor Forcing bid may be applied:
In the card game bridge, CoCa or Comfy Canapé is a conventional defense against opposing 1NT openings. When playing CoCa, over a 1NT opening of the opponents, both a double as well as a 2♣ overcall are conventional and establish spades and hearts, respectively as anchor suits. Higher overcalls can be either natural, or conventional.
The Carrot 1NT is a contract bridge convention, in which a 1NT opening bid shows a balanced hand 13-17 hcp. With 13-14 hcp, the opener may not have a 4-card major. With 15-17 hcp, all balanced hands may be opened 1NT.
OKbridge 2/1 is a duplicate bridge bidding system combining two-over-one game-forcing and Walsh bidding methods.
Mohan is a bridge convention used to intervene over opponents' 1NT opening. Typically it only applies if the opponents' are using a weak 1NT opening. Its invention is usually attributed to John Mohan.
Astro is a contract bridge bidding convention used to intervene over an opponent's one notrump (1NT) opening bid. The name is derived from the initials of the surnames of its inventors - Paul Allinger, Roger Stern and Lawrence Rosler.
Five-card majors is a contract bridge bidding treatment common to many modern bidding systems. Its basic tenet is that an opening bid of one-of-a-major in first and second position guarantees at least five cards in that major. This method has become standard in North American tournament play, but European methods vary.
