Kawa

Kawa 「河」 is formed by the discarded tiles. In Japanese, it literally means "river", and it can also be referred to as the "pond". Regardless of reference, the tile discards provide players with different information regarding the current state of the hand. For defensive play, players rely on the discards to determine safe tiles. They can also be used to determine probable hands of other players, especially when particular yaku are sought for.