noun
winning hand with only terminals and honors
A mahjong yaku: a hand composed entirely of terminal tiles (1s and 9s) and honor tiles (winds and dragons).
from Chinese hùn lǎo tóu
混老頭は、么九牌だけで作る役です。
Honrōtō is a yaku made only with terminals and honors.
彼は混老頭を狙って、端牌と字牌だけを集めた。
He aimed for honrōtō and collected only terminals and honors.
混一色 is a hand with one suit plus honors, while 混老頭 is restricted to terminals and honors only.
From Chinese 混老頭 (hùn lǎo tóu), literally 'mixed old head', referring to a hand mixing terminals (old) and honors (head).