I - Poker Terms
Idiot End, Ignorant End - The lowest possible straight given the community cards. For example, if the board is 678, a player holding 45 has the bottom end of the straight. Also bottom end.
Implied Pot Odds, Implied Odds - These are pot odds that also inlude what you can expect to win from future betting if you hit your draw. For example, "I didn't have the correct pot odds to call with my gutshot straight draw but I put my opponent on a set and if I could hit my straight he would pay me off with his whole stack, giving me good implied odds, so I called."
Improve - To achieve a better hand than what you currently have by either exchanging cards in draw poker, community cards landing in community card games; such as Holdem or cards landing on your board in Stud. For example, "I didn't think he was bluffing, so I decided not to call unless I improved on the the river."
Initiative - The last player to bet or raise is said to have the initiative. Having the initiative has advantages. Players are more likely to check to the player with the initiative and they have tougher decisions.
Inside Straight Draw - A straight draw with only four outs to improve. For example, in Holdem 86 with a board of 459 is an inside straight draw because only the 7 will give you a straight. Also belly buster or gutshot. See also double gutshot.
In Position, IP - The last player to act on a betting round. This gives the player a huge advantage because he gets to see what everyone else does first. For example, in Holdem preflop the big blind has position; however postflop the button has position (unless he has folded and then the next player still in the hand to his right has position). See positions at the table. See also out of position.
Insta-call - To call very qickly without hesitation. This is usally a sign of strength and after an all-in will likely be with the nuts. Also snap call.
Insurance - A player potentially facing a big loss betting on himself losing in order to cover his loss or lower the risk. For example, a player going all-in in Holdem with AA against KK may be affraid that a king will land on the flop, so he makes an insurance bet with another player, so that he cannot lose whatever the outcome.
In the Middle - In the middle of action. That is having players' bet and raise before and after you.
In the Money, ITM - To place high enough in a poker tournament to get some prize money.
In Turn - A player, or an action, is in turn if that player is supossed to act at that time.
Irregular Declaration - An action taken by a player that is not a straightforward declaration of intent, but is reasonably interpreted as an action by other players. For example, tapping the table to signify a check or pointing a thumb up to signify a raise. House rules or dealer discretion determine whether the action counts should a player deny his action.
Irregularity - Any abnormal conditions in play. For example, unexpectedly exposed cards, wrong number of cards dealt etc.
Isolation - A raise intended to make one or more players fold to allow you to play heads-up against a specific opponent. Isolation raises are sometimes used by experienced players when there is a weak opponent in the pot.