Definition of 亡羊補牢 (ぼうようほろう)

noun
locking the barn door after the horse has bolted, doing something too late, mending the pen after the sheep are lost(yojijukugo)
Related Kanji
deceased, the late, dying, perish
sheep
supplement, supply, make good, offset, compensate, assistant, learner
prison, jail, hardness