A chukka lasts seven minutes of play, plus thirty seconds of grace. The bell rings at seven; play stops when the ball goes out or at seven and a half.
Six chukkas is the high-goal standard, with a ten-minute half-time. Between chukkas players change horses: a pony plays at most two chukkas a match, with rest in between.
The word itself comes from the Hindi chakkar, a circle, and the game from the valley of Manipur, where British officers first played it in the 1850s.
