In general, the term 'trips' refers to three of a kind.
In games that involve community cards, three of a kind can be referred to as trips if the hand is composed of two community cards that make a pair and a matching hole card. In contrast, a set consists of two hole cards that make a pair and a matching community card.
Example (Texas Hold'em):
The player has three of a kind, fives. As two of the three fives are community cards and only one of the fives belongs to the player's hole cards, this three of a kind can also be called trips.