Question

Many nineteenth-century American coinages are metaphors. What is meant by dark horse?

Answer 1

Answer:

an unexpected winner.

Explanation:

Answer 2

A dark horse is an unexpected winner. Someone who wins something completely unexpectedly, out of nowhere, no one would have believed that they would be a winner. The expression was originally used in horse racing as slang to describe a horse that wins that no one would have bet on to win.