round wind tiles
Mahjong term: tiles that match the current round wind (場風). These tiles can be used to form a yaku (役) when they match the player's seat wind as well, or when they are part of a pung/kong of the round wind.
I called pung on the round wind tile and secured the yaku.
In the East round, East tiles are the round wind tiles.
Compound of 場風 (round wind) + 牌 (tile).