In the card game "contract bridge", a splinter bid is a convention whereby a double jump response in a side-suit indicates excellent support (at least four cards), a singleton or void in that side-suit (but preferably not the ace or king), and at least game-going strength. [1] Some partnerships agree that the maximum strength can be only that necessary to reach a game contract; stronger holdings with major suit support instead might temporize with a Jacoby 2NT bid.
The idea was developed independently in 1963 by David Cliff, the first to write about it, and Dorothy Hayden Truscott; it grew out of two earlier bidding tools, the Fragment bid and the Void-Showing bid. [2]
For example, a four clubs (4♣) response to a one heart (1♥) opening establishes hearts as trump suit and indicates a singleton or void in clubs. Different bidding systems may specify different strengths for responder's hand, e.g. 10-12 high card points (HCP), 10-14 or 11-15, for a splinter. With a strong hand, a responder and opener may be able to make slam on sheer strength, so splinters by responder are best restricted to hands containing a fairly narrow HCP range and a void or a small singleton in the splintered suit. A singleton honor is frowned upon. Although they consume bidding space, splinter bids are very descriptive as they help partner to reevaluate his/her hand: soft honors (a king, queen or jack) in the splinter suit lose value, while honors in the other three suits gain value.
In some positions if a simple bid of the suit would be forcing then a single jump can be a splinter. For example, in a system where 1♥–2♣; 2♦ is a forcing sequence, 1♥–2♣; 3♦ may be used as a splinter. (However, this approach would require a specific agreement in advance—many players use this sequence to denote a strong two-suiter.) Some partnerships use certain single jumps as "mini-splinters" that promise less strength, allowing partner to choose between part-score and game rather than between game and slam.
The short suit in a splinter hand is preferably a small singleton, though it can occasionally be a singleton honor or a void. The idea is that partner can easily tell if he has wasted values in the splinter suit; for example, Axxx is ideal whereas KJ9x is almost worthless.
Opener can also make a splinter bid to agree responder's suit if he is strong enough to be able to force to game if responder was minimum for his bid; see example 2 below. Typically, opener would have 15-18 points for this sequence.
The four diamond bids in the following bidding sequences (with East-West passing throughout) are generally agreed to be splinter bids establishing spades as the trump suit:
| North | South |
|---|---|
| 1♠ | 4♦ |
| North | South |
|---|---|
| 1♣ | 1♠ |
| 4♦ |
| North | South |
|---|---|
| 1♣ | 1♥ |
| 1♠ | 4♦ |
A splinter may occur at the three level. In the following auction, South is showing acceptance of hearts and a singleton in spades.
| North | South |
|---|---|
| 1♥ | 3♠ |
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.
2/1 game forcing is a bidding system in modern contract bridge structured around the following responses to a one-level opening bid:
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 most bridge 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.
The weak two bid is a common treatment used in the game of contract bridge, where an opening bid of two diamonds, hearts or spades signifies a weak hand with a long suit. It is used in combination with the strong two clubs bid and is a form of preemptive bid. The term refers to an opening bid, and is not to be confused with the "weak jump overcall", which denotes a similar type of hand, but is bid over an opponent's opening bid.
In the card game contract bridge, a takeout double is a low-level conventional call of "Double" over an opponent's bid as a request for partner to bid his best of the unbid suits. The most common takeout double is after an opponent's opening bid of one of a suit where the double shows a hand with opening values, support for all three unbid suits and shortness in the suit doubled. Normally, the partner of the doubler must bid his best suit but may pass if (a) his right hand opponent intervenes or (b) on the more rare occasions when his hand is such that he wishes to convert the takeout double to a penalty double.
Jacoby 2NT is a bridge convention in which a bid of 2NT over partner's opening bid of one heart or one spade shows a hand with both
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.
In contract bridge, various bidding systems have been devised to enable partners to describe their hands to each other so that they may reach the optimum contract. Key to this process is that players evaluate and re-evaluate the trick-taking potential of their hands as the auction proceeds and additional information about partner's hand and the opponent's hands becomes available.
Bridge bidding systems that incorporate a strong 2 clubs opening bid include modern Standard American, standard Acol, 2/1 game forcing and many others.
Slam-seeking conventions are codified artificial bids used in the card game contract bridge. Bidding and making a small slam or grand slam yields high bonuses ranging from 500 to 1500 points. However, the risk is also high as failure to fulfill the slam contract also means failure to score the bonus points for a game (300-500). Conventions have been devised to maximise the opportunity for success whilst minimising the risk of failure.
In contract bridge, Last Train refers to a bid just below game level in the agreed suit. A Last Train bid is typically made in a bidding sequence in which one of the partners has already indicated slam interest.
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.
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:
Bridge base basic, also known as BBO basic, is a bidding system for the game of bridge based on the Standard American Yellow Card (SAYC). It is simplified, suitable for beginners, and widely used in internet bridge, particularly on Bridge Base Online. It is taught in Fred Gitelman's educational software called Learn to Play Bridge that is available as a free download from the American Contract Bridge League's website.
Transfer Walsh is a bidding convention used in contract bridge. After a 1♣ opening bid, responses of 1♦ and 1♥ show heart and spade suits respectively. The "Walsh" terminology refers to the fact that these bids may conceal an equal or longer diamond suit. It allows opener to play a greater proportion of major-suit and no-trump contracts, particularly when using five-card majors.