What is the origin of the idiom "on the nose" and when to use it?

The idiom "on the nose" has origins in horse racing. In this context, "on the nose" referred to a bet placed on a horse to win, with the expectation that the chosen horse would cross the finish line first. The term gradually evolved to describe something that is precise, accurate, or exactly right, similar to predicting the winner of a race. People use the phrase "on the nose" to mean that something is exactly correct or accurate without any deviation or error.