The idiom "A DARK HORSE" means?

The idiom "A DARK HORSE" means?

Explanation

The idiom "a dark horse" means an unexpected winner.

It refers to someone who achieves success or wins a competition unexpectedly.

It often surprising others with their abilities or achievements.

A Dark Horse ایسا شخص جو غیر مقبول ہو، اچانک منظر عام پر آئے اور کامیاب ہوجائے