To beat a dead horse means to bring up a previously settled issue. Any further discussion on it might be seen as pointless because the issue was already talked about before.
Example: Like I said last week, our trip to Vancouver is on hold until next year, so stop beating a dead horse and asking me about it.
The Origin of ‘Beating a Dead Horse’:
There are several phrases and sayings in use today that originated from horse racing. It is possible that this one also comes from it. How so? Well, during a horse race, a jockey usually has access to a riding crop, which kind of looks like a miniature whip. The jockey uses the riding crop to hit or “beat” the horse (typically on the thigh, I believe) for purpose of getting them to run faster.
While there is controversy involved with how horses are treated during races, there is a purpose to “beating” a horse during this activity—more speed. However, what would be the point of beating a dead horse? There wouldn’t be one; it’d be pointless! So while beating a living horse serves a purpose, beating a dead one would be futile.
Anyways, this saying dates back to at least the year 1859. A form of it makes an appearance in the London newspaper Watchman And Wesleyan Advertiser. There’s an article from the newspaper that reads:
“It was notorious that Mr.Bright was dissatisfied with his winter reform campaign and rumor said that he had given up his effort with the exclamation that it was like flogging a dead horse.”
The word ‘flogging’ is just another word for beating.
- Why do you insist on beating a dead horse by bringing up these old problems of ours?
- Blake wanted to debate with his friends about which of the two cars had better gas mileage, but they said the argument would be like beating a dead horse.
Note: While this is not the case for all phrases and sayings, sometimes their origin is unknown. When that happens, if there are explanations floating around that talk about how it might have originated, then I’ll probably mention it. If no explanation is listed on the page, well, there should still be an old quote of the idiom being used. This can give you an idea on how old it is.