noun
dead horse
Literal meaning: a horse that has died. Can be used in proverbial or figurative contexts.
道端に死に馬が倒れていた。
A dead horse was lying by the roadside.
noun
stupid horse; useless horse; crowbait
Derogatory term for a horse that is considered worthless or incompetent. Often used in insults or complaints about a horse's performance.
あの死に馬はまたレースで最下位だった。
That useless horse came in last again in the race.
こんな死に馬に餌をやるのは無駄だ。
It's a waste to feed a crowbait like this.