(mahjong) a winning hand using special rules; worth 48,000 points if the winning player is on the East (dealer) side or 32,000 points otherwise

(figuratively) driving force

(Japanese fiction, pornography) the one who fucks other characters

(military) reserve service

one who sets fire / (by extension) one responsible for something's popularity, etc.

Kyūjitai form of 暗号 (“code; cipher”)

absolute darkness / (Buddhism) a complete lack of virtue or wisdom / (color) pure black

dim, faint, dimly lit

(martial arts, weaponry) a hidden weapon

culvert, underground drainage ditch; underground drain; covered drain, underdrain