some lingo that i've picked up (texas holdem poker):
community cards: the five cards available to all players
under the gun: the player immeadiately after the two blinds, effectively the first person in the first round of betting (pre-flop) who gets to make a decision (call the big blind, fold, raise)
if it is your turn to make a decision (bet, raise, call, check, re-raise, fold) then the 'action' is on you
early position: the players who act first in a hand (if there are five players, the first couple could be said to be in early position). Early position is weaker than late position because the later position players in a hand get to see what you do before they have to act.
Hole cards: your two private cards
When your hole cards are two aces you have 'pocket rockets'
When your hole cards are an ace and a king you have 'big slick'
when your hole cards are a nine and a five you have 'dolly parton'
when your hole cards are two eights you have 'two snowmen'
when your hole cards are a king and a jack you have 'kojak'
when your hole cards are both queens you have 'ladies' or 'siegfried and roy'
There are two terms for three-of-a-kind, but not everyone uses them consistently. As far as I can tell, the term 'a set' is used when you have three-of-a-kind where two of them are your hole cards. The term 'trips' is used when you have three-of-a-kind where only one of them is in your hole cards (and therefore the other two are in the community cards).
You may hear the term 'a dominated hand'. Say you have a Jack and a five, and bob has a Jack and an eight: your hand is dominated because both you and bob have the same high hole card (a Jack), but your other hole card is lower than bobs. This is bad for you because if a Jack comes up on the community cards then you both have a pair of jacks, but bob has a better kicker (his eight beats your five).
The term 'side-pot' is used when one player is 'all-in' but other players have more money and wish to continue betting with eachother: if the all-in player wins, he/she takes only the money equivalent to his/her all-in bet from those players that called it, the side-pot is then decided between those players that stayed in the hand (who had more money left after calling the all-in player).
bad beat: you loose a hand after playing well in the hand (betting well, sussing out your oppenents hands) but someone gets really lucky (usually the river card gives them the best hand but the odds were well against them getting that card on the river)
drawing dead: no matter what community cards appear, you will not have the strongest hand even if you hit your draw
inside/gutshot straight draw: you need one card to make a straight and it can only be one type of card (you have 4,5,7,8 so you must get a 6 to make your straight)
outside straight draw: you need one card to make a staright but it can be one of two cards (you have 8,9,10,J so you need either a 7 or a Q to make your stairght)
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The terms bet, check, raise, re-raise, fold, call are the actions that you can perform. They seem straight forward but if you want to get pedantic, here is what I believe the correct definitions as follows:
Fold: you throw away your cards and take no more part in the current hand
Call: there is money in the pot which you need to at least match to stay in the hand. If you simply match the amount then you are 'calling'
Check: If you can stay in the hand without putting any money in then you can 'check' (if all players check in a round it is common for the round to be said to be checked down, or 'everybody checked down'). Strictly speaking, checking can only be done in the last three betting rounds. In other words, checking is not possible in the first round (pre-flop). Though, it is common to see the big-blind player saying 'check' in the first (pre-flop) round if no-one has raised the big-blind amount and the big-blind player wants to stay in the hand but without putting any more money in than the compulsory big-bling that they have put in (and then you would see the flop). Strictly speaking, this action is known as a 'no-bet' (or so i've discovered over the years) rather than a 'check'.
Bet: ok, here's the really confusing one lol. The word bet is generally used when a player puts money in the pot, be it calling or raising. Strictly speaking a 'bet' in texas holdem is only performed by the first player in a round to put money in. The only 'bet' in the first (pre-flop) round are the small and big blinds (the small blind could be considered as the first bet, the big blind is also known as a compulsory 'bet' by convention). In the subsequent rounds, only the first player to put money in the pot makes a 'bet'. So bob, fred, john and dave are in the second round of betting: bob checks (puts no money in but stays in the hand), fred makes a bet, john calls freds bet, dave folds, bob calls. Even though john and bob both put money in after fred, these are not strictly called 'bets' - they are calls.
Raise: when you match the current amount and raise it higher. There is a very important convention you must follow here. Say the current amount is 10 quid, you want to raise it up to 15 quid. You cannot say "I call your 10 quid and raise it to 15 quid". You have to say "I raise to 15 quid". This is because if you say "I call your 10 quid......." you may see a reaction on other players who think you have simply called, but then you add that you are raising - this is considered unacceptable. If you are going to raise, dont say the word "call" at all, simply say "raise" or "I raise to".
Re-raise: when you raise a previous raise