Definition: A 'Counterfeit' card is one that doesn't improve a player's hand, but instead, makes it worse.
For instance, in Texas Hold'em, if you have 6-7 and get two pair on the flop, but then a higher pair falls on the board -- say two queens, your two pair is counterfeited, since now you now have queens and sevens as your best hand -- but everyone has those queens, so your hand doesn't look so good anymore.
This is also commonly used in Omaha hi-lo, because low poker hands are often counterfeited by cards that fall on the turn and river.
For instance, in Texas Hold'em, if you have 6-7 and get two pair on the flop, but then a higher pair falls on the board -- say two queens, your two pair is counterfeited, since now you now have queens and sevens as your best hand -- but everyone has those queens, so your hand doesn't look so good anymore.
This is also commonly used in Omaha hi-lo, because low poker hands are often counterfeited by cards that fall on the turn and river.
