Glossary of Contract Bridge Terms - O

O

Obligatory

1) Of a finesse: A duck, made in the hope that a high card will fall. For example, declarer holds ♥K432 opposite dummy's ♥Q765. The ♥2 is led to the ♥Q, which wins. Declarer now leads dummy's ♥5 and RHO follows with the ♥J. Declarer ducks, hoping that LHO must now play the ♥A. The play is obligatory because given the first heart trick, no other play can yield three tricks.

2) Of a falsecard: A falsecard that, like an obligatory finesse, cannot lose and might gain. An example is the play of the card that one is known to hold (for example, the play of a queen after it has been successfully finessed).

Odd

Specifying a level. To make 4♥ is to make four-odd.

Odd-even discards

A defensive carding scheme under which the play of an odd-numbered card is encouraging and that of an even-numbered card is discouraging. The rank of the card may be used to show suit preference.

Odd tricks

The number of tricks above six (the book) that are taken by declarer.

Off

1) (Slang) Down, or set. "We're off two" means "We have made two fewer tricks than our contract."

2) (Slang) offside.

Off shape

Having a distribution that does not quite conform to that suggested by a bid, such as an opening bid of 1NT with 2=2=6=3 shape, or a weak-two bid with a seven card suit.

Off the top

Said of some number of tricks that can be lost or won without gaining or losing the lead. "There were eleven tricks off the top in spades", to mean that declarer could take eleven tricks without interruption; or, "We're down off the top", to mean that the defenders can take at least four immediate tricks against 4♥.

Offside

Unfavorably located, from the point of view of the player taking a finesse. If East holds the ♣K and North the ♣AQ, from South's point of view the ♣K is offside. Cf. onside.

Olympiad

A world bridge championship held every four years under the auspices of the World Bridge Federation.

On

1) Makeable. A contract that can be made is said to be on.

2) Onside.

3) (Suffix) In rubber bridge, preceded by a number that indicates progress toward game. If one has 40 points Below the line, one has 40-on.

One club system

A bidding system that uses a bid of 1♣ as artificial and forcing, but not necessarily strong.

One over one

To an opening one-bid, any one-level response in a suit; that is, one of a higher suit in response to opening one of a lower suit. Contrast two over one.

One round force

A bid that requests partner to ensure that the bidding continue for at least one more round. If partner's RHO bids, partner may pass, but is otherwise expected to bid.

See also Forcing bid, Game force and Grand slam force.

One-suiter

A hand with only one long suit, normally refers to a hand with a six card or longer suit.

Onside

Favorably located, from the point of view of the player taking a finesse. If West holds the ♣K and North the ♣AQ, then from South's point of view the ♣K is onside. Cf. Offside.

Open

1) In the auction: To start the bidding by making the first call other than Pass.

2) Of a room used at a team event: allowing spectators. Normally at least one of two rooms is closed to spectators.

3) Of an event: not restricting entries in some way that is implicit. So participation in an open event is unrestricted in at least one respect:

a) not by invitation only (invitational event)

b) not by qualification in a preceding event or qualifier

c) not by representation of geographic zones, nations, cities, clubs, etc; nor by requirement that pair or team members share geographic residence, club membership, etc (national event, etc)

d) not by age, sex, or playing record (seniors, Masters, etc).

Open is generally ambiguous but it does have the last sense (d) in the names of WBF world championship events, where the relevant Categories are Youth (with subcategories), Seniors, Women, and Open. For the WBF, transnational means open in sense (c).

Opener

The player who makes the opening bid.

Opener's rebid

Opener's second bid.

Opening bid

The first bid in the auction.

Opening lead

The first card led by defenders. The dummy is not faced until after the opening lead, which makes the choice of opening lead more difficult than other leads. The opening lead can determine the outcome of the deal.

Opening leader

The declarer's LHO, who always makes the opening lead.

Opponent

A member of the other partnership or team.

Optimum contract

In unopposed bidding, the contract that cannot be improved upon by further bidding, nor could have been improved upon by taking a different line in earlier bidding. The contract is regarded as optimum because it offers the maximum score while minimizing the risk of failure.

Our hand

(Informal) A hand on which "our" side can take more tricks than their side.

Out-of-the-blue cue bid

See Advance cue bid.

Over

See In back of.

Overbid

1) (Noun) A bid that overstates a hand's strength.

2) (Verb) To bid voluntarily to a contract that the partnership cannot make.

3) (Verb) To bid too high, irrespective of the result.

Overboard

(Slang) Having overbid.

Overcall

The first bid made by one of opener's opponents unless they intervene first by a double.

Overcaller

The player making an overcall. Compare with advancer.

Overruff

To ruff with a higher trump following a prior ruff on the same trick.

Overtake

To play a card higher than the winning card played by partner, unnecessary to win the trick but necessary to gain the lead.

Overtrick

A trick taken by declarer beyond the number of tricks required by the contract.