four concealed triplets; four concealed pungs
A yakuman hand in mahjong consisting of four concealed triplets (three-of-a-kinds) and a pair, all drawn without claiming discards. The hand may be won by self-draw or, in some rules, by a discard on a single wait.
from Chinese sì àn kè
Four concealed triplets is one of the most difficult yakuman hands.
He won with a self-drawn four concealed triplets and turned the game around.
From Chinese 四暗刻 (sì àn kè), literally 'four concealed triplets'. The reading スーアンコー reflects the Chinese-derived mahjong terminology used in Japanese.