Question

What does 'horse of another color' mean?

Answer 1

This term probably derives from a phrase coined by Shakespeare, who wrote “a horse of that color”, meaning “the same matter” rather than a different one. By the mid-1800s the term was used to point out difference rather than likeness.

Answer 2

'Horse of another color' is the opposite expression from Shakespeare's 'a horse of that color' in the Twelfth Night Act 2 Scene 3 where Maria told Sir Toby Belch that her purpose was indeed a horse of that color which meant that Sir Toby Belch got the same idea as hers. So, 'horse of another color' is an idea different from the other.