CHAPTER I
Definitions 

Adjusted Score 

An arbitrary score awarded by the Director (see Law 12 ). It is either "artificial" or "assigned".
1. An artificial adjusted score is one awarded in lieu of a result because no result can be obtained or estimated for a particular deal (e.g., when an irregularity prevents play of a deal).
2. An assigned adjusted score is awarded to one side, or to both sides, to be the result of the deal in place of the result actually obtained after an irregularity.

Alert 

A notification, whose form may be specified by a sponsoring organisation, to the effect that opponents may be in need of an explanation.

Auction 

1. The process of determining the contract by means of successive calls.
2. The aggregate of calls made (see Law 17E).

Bid 

An undertaking to win at least a specified number of odd tricks in a specified denomination.

Board 

1. A duplicate board as described in Law 2 .
2. The four hands as originally dealt and placed in a duplicate board for play during that session.

Call 

Any bid, double, redouble or pass.

Contestant 

In an individual event, a player; in a pair event, two players playing as partners throughout the event; in a team event, four or more players playing as teammates.

Contract 

The undertaking by declarer's side to win, at the denomination named, the number of odd tricks specified in the final bid, whether undoubled, doubled, or redoubled.

Convention  

1. A call that, by partnership agreement, conveys a meaning other than willingness to play in the denomination named (or in the last denomination named), or high-card strength or length (three cards or more) there. However, an agreement as to overall strength does not make a call a convention.
2. Defender's play that serves to convey a meaning by agreement rather than inference.

Deal 

1. The distribution of the pack to form the hands of the four players.
2. The cards so distributed considered as a unit, including the auction and play thereof.

Declarer 

The player who, for the side that makes the final bid, first bid the denomination named in that bid. He becomes declarer when the opening lead is faced (but see Law 54A when the opening lead is made out of turn).

Defender 

An opponent of (presumed) declarer.

Denomination 

The suit or notrump specified in a bid.

Director 

A person designated to supervise a duplicate bridge contest and to apply these Laws.

Double 

A call over an opponent's bid increasing the scoring value of fulfilled or defeated contracts (see Law 19 and Law 77).

Dummy 

1. Declarer's partner. He becomes dummy when the opening lead is faced.
2. Declarer's partner's cards, once they are spread on the table after the opening lead.

Event

A contest of one or more sessions.

Follow Suit 

Play a card of the suit that has been led.

Game 

100 or more trick points scored on one deal.

Hand 

The cards originally dealt to a player, or the remaining portion thereof.

Honour 

Any Ace, King, Queen, Jack or 10.

International Matchpoint (IMP) 

A unit of scoring awarded according to a schedule established in Law 78B .

Irregularity 

A deviation from the correct procedures set forth in the Laws.

Lead 

The first card played to a trick.

LHO 

Left-hand opponent.

Matchpoint 

A unit of scoring awarded to a contestant as a result of comparison with one or more other scores.

Odd Trick 

Each trick to be won by declarer's side in excess of six.

Opening Lead 

The card led to the first trick.

Opponent 

A player of the other side; a member of the partnership to which one is opposed.

Overtrick 

Each trick won by declarer's side in excess of the contract.

Pack 

The 52 playing cards with which the game of Contract Bridge is played.

Partner 

The player with whom one plays as a side against the other two players.

Partscore 

90 or fewer trick points scored on one deal.

Pass 

A call specifying that a player does not, at that turn, elect to bid, double or redouble.

Play 

1. The contribution of a card from one's hand to a trick, including the first card, which is the lead.
2. The aggregate of plays made.
3. The period during which the cards are played.
4. The aggregate of the calls and plays on a board.

Premium Points 

Any points earned other than trick points (see Law 77).

Psychic Call 

A deliberate and gross misstatement of honour strength or suit length.

Rectification 

Adjustment made to permit the auction or play to proceed as normally as possible after an irregularity has occurred.

Redouble 

A call over an opponent's double, increasing the scoring value of fulfilled or defeated contracts (see Law 19 and Law 77).

Revoke 

The play of a card of another suit by a player who is able to follow suit or to comply with a lead penalty.

RHO 

Right-hand opponent.

Rotation 

The clockwise order in which the deal and the right to call or play progresses.

Round 

A part of a session played without progression of players.

Session 

An extended period of play during which a number of boards, specified by the sponsoring organisation, is scheduled to be played.

Side 

Two players who constitute a partnership against the other two players.

Slam  

A contract to win six odd tricks (called Small Slam) or to win seven odd tricks (called Grand Slam).

Suit 

One of four groups of cards in the pack, each group comprising thirteen cards and having a characteristic symbol: spades (), hearts (), diamonds (), clubs ().

Team 

Two or more pairs playing in different directions at different tables, but for a common score (applicable regulations may permit teams of more than four members).

Trick 

The unit by which the outcome of the contract is determined, regularly consisting of four cards, one contributed by each player in rotation, beginning with the lead.

Trick Points 

Points scored by declarer's side for fulfilling the contract (see Law 77).

Trump 

Each card of the suit, if any, named in the contract.

Turn

The correct time at which a player may call or play.

Undertrick 

Each trick by which declarer's side falls short of fulfilling the contract (see Law 77).

Vulnerability 

The conditions for assigning premiums and undertrick penalties (see Law 77).