亡羊補牢 ぼうようほろう Meanings Noun locking the barn door after the horse has bolted; doing something too late (literally: mending the pen after the sheep are lost) Kanji 亡 pass away. Read as ボウ. 羊 sheep. Read as ヨウ. 補 supplement 牢 prison; jail; hardness. Read as ロウ. Word lists Yojijukugo (四字熟語) Jinuma: Japanese Dictionary · Word lists