The trips poker slang term is just another saying for a three-of-a-kind hand. More specifically, it’s when you make a three-of-a-kind hand with one card in your hand and two cards on the community board.
For example, you have a king and a queen in your hand, and the flop comes two queens and a deuce. You now have trip queens.
Many players confuse trips with another term – set. But, the main difference between the two is that a set is when you already have a pocket pair and turn it into a three-of-a-kind hand with the help of one community card.