Odds: the chance of something happening.
Offsuit: cards which do not have the same suit.
Omaha: a form of poker that is very popular.
On the Button: the last player who has to make a decision at a table.
Open: to make the opening bet, first bet.
Open-ended Straight: when a player has 4 out of 5 cards for a straight but is waiting for the last one.
Open Card: a card that is dealt face up on a table.
Open Pair: a pair that has been dealt face up on a table..
Out Button: a small plastic disc that is placed in front of the player who wishes to sit out a round.
Outs: the number of cards left in a deck that can be useful.
Overpair: when a player is holding a pair that is higher than any cards on the table.