Poker
Nut
The nut, or the nuts, is the best possible hand on the board at that moment. A player with the nuts cannot be beaten, unless the board changes.
Nut Advantage
Nut advantage is a situation in which one player is more likely than the other to hold the strongest hands on a board. It is one of the three main types of advantage in a hand, alongside positional advantage and range advantage.
Nut Flush
A nut flush is the highest possible flush on the board. It usually includes the ace of the suit, and nobody can have a higher flush.
Nut Flush Draw
A nut flush draw is four cards of one suit including the ace, needing one more card of that suit to make the highest possible flush.
Nut Low
The nut low is the best possible low hand in a high-low split game. In most games it is the wheel, A-2-3-4-5, and in deuce-to-seven lowball it is 7-5-4-3-2.
Nuts
The nuts is the best possible hand at that moment, given the board. A player who has the nuts cannot be beaten, unless a new card changes the board. The word is also used for the best hand of a type, such as the nut flush.
Odds
Odds are the likelihood of an event, often written as a ratio. In poker, they are used to decide whether a call, fold or raise is profitable.
Odds Against
Odds against are the number of failures for each success. If something has odds of 4 to 1 against, it fails four times for every time it succeeds.
Odds For
Odds for are the number of attempts per success. If the odds for an event are 5 to 1, it happens once in five attempts.
Odds On
Odds on describes a situation in which an event is more likely to happen than not. A favorite is said to be odds on.
Offsuit (o)
Offsuit means that two cards are of different suits. In Hold'em, an offsuit starting hand has hole cards of different suits, and is a little weaker than the same hand suited. In notation, it is written with an 'o', such as AKo.
Omaha
Omaha is a poker game similar to Hold'em in which each player gets four hole cards and must use exactly two of them with exactly three of the five community cards. The most popular forms are pot-limit Omaha and Omaha hi-lo.
On the Button
On the button means being in the dealer position, the player who acts last after the flop. The button marks this seat and moves clockwise after each hand.
On The Come
On the come means that a player does not yet have a complete hand, such as when he holds a drawing hand. He is betting or calling on the come, in the hope of completing it.
On Tilt
On tilt describes a player whose emotions harm his play, often after a bad beat or a series of losses. He plays worse than usual, often with too much aggression.
One Time
'One time' is a plea that players say aloud when they need a specific card to come, as in 'one time!' on the river. It is a way of asking for luck, rather than a play or a rule.
One-Chip-Behind
One-chip-behind means betting or raising almost your entire stack while keeping one chip unbet. Unless you have declared all-in, that chip remains available for a later decision.
One‑Chip Rule
The one-chip rule says that a player who puts a single chip in the pot, when facing a bet, is making a call and not a raise, unless he says 'raise' first. It applies even if the chip is of a higher value than the call.
One‑End
One-end, or one-way straight, is a four-card straight that is open only at one end, such as jack, queen, king, ace.
One‑Gap (One‑Gapper)
A one-gap hand, or one-gapper, is a starting hand whose two cards are two ranks apart, with one rank missing between them, such as J-9 or 6-4. It can make a straight only in a few ways.
One‑Outer
A one-outer is a situation in which a player has only one card left in the deck that can make him win the hand. He is a huge underdog.
One‑Way Straight
A one-way straight, or one-end straight draw, is a four-card straight draw that can be completed on only one end, such as jack, queen, king, ace. It has only four outs.
Open
To open is to be the first player to bet in a betting round. Before the flop it means to be the first to raise. An open raise is the first raise in the pot.
Open at Both Ends
Open at both ends means a four-card sequence that can become a straight with two different cards, one at each end. It is also called an open-ended draw.
Open Card
An open card is a card dealt face up. In stud and some other games, open cards are seen by all players.
Open End
An open end is a four-card sequence that can be made into a straight by two different cards. It is also called open at both ends or an open-ended draw.
Open Game
An open game is a game in which anyone can play. It is not restricted to a private group.
Open Limp
An open limp is entering the pot before the flop by only calling the big blind when nobody else has entered. You are the first player in, and you do not raise.
Open Pair
An open pair is a pair that has been dealt face up, so all players can see it. It is common in stud games.
Open Poker
Open poker means poker games in which some of the cards are dealt face up, such as seven-card stud. It is the opposite of closed poker, in which all cards are hidden.
Open Seat
An open seat is a seat at a poker table that is unoccupied and available for a new player to join the game.
Open‑Ended Straight Draw
An open-ended straight draw is four cards in a row that need one specific card at either end to complete a straight. It has eight outs, so it comes in about one time in three by the river.