A strenuous and risky athletic game, played by teams of four, that is often mentioned by Starfleet personnel in the twenty-fourth century but never shown in full.
Parrises squares is first mentioned in the episode 11001001, when Worf, Tasha Yar and other officers of the Enterprise-D set off in padded uniforms to play a team from Starbase 74, and Worf makes clear he intends to win.
The sport has a reputation for injuries. In Future Imperfect, the boy presented to Riker as his son breaks an arm playing it, and several other episodes refer to players being hurt or to people thought too old to take part.
References continue in Deep Space Nine and Voyager, the latter mentioning a piece of equipment called an ion mallet. The rules are never explained on screen, which has left the game as one of the franchise's longest-running pieces of background detail.