"Sucking out" is a term poker players use to identify a player who stays in a hand until the last card is dealt and wins. The player who wins on the last card is referred to as a "suck-out" player. The odds of a suck-out player winning are extremely low but occasionally they get lucky and do win. I recently played in a Texas Hold 'em tournament and was dealt a pair of Jacks as hole cards. When the flop came (three cards dealt up) there was another Jack. Based on the three community cards I could see, someone else could have a straight, which would beat me.
For some crazy reason, I stayed in. The fourth card (turn card) was of no help to me but no doubt made a straight for someone else. I stayed in again for the last card (river card) and to my surprise it was another Jack. Three of us were left in the hand and I was in last position to bet. The first player bet and the second player raised. I called and to my glee the first player re-raised and the second player re-raised again. I decided to go all in and they called me. My opponents couldn't wait to turn their cards over showing both had straights. They looked at my four Jacks in amazement. "You sucked out," said one of the players. The other player didn't say a word, stood up and left. Yup, I had sucked out.