This is not an idiom that I have ever heard. Perhaps you mean an arm AND a leg, which is an exaggerated way of saying something is really expensive.
(The idiom means "expensive" or "overpriced.")"That waterfront property will cost me an arm and a leg.""Don't lose that watch, because it cost me an arm and a leg."
more then you could give or pay then priceless bodily limbs, that are expensive on black market"An arm and a leg" is an idiom that means an exorbitant or very high price paid for something. "Jeeze, did you see that they're charging an arm and a leg for a gallon of gas these days!"
Oh yes, that is an idiom. There are no transactions in which someone literally gives one of his or her arms and legs as payment.
American slang from 1960's, possibly from Vietnam, meaning 'costing a lot.'
Fibrosarcomas originate in the ends of the bones in the arm or leg, and then spread to soft tissue.
Most leg muscles and arm muscles, some muscles in the head, and most internal muscles.
your leg
get a leg up on
I was just pulling your leg when I told you I won the lottery; it was just a joke to see your reaction.
No, because you have used the term incorrectly. The idiom is YOU'RE pulling my leg, as in YOU ARE doing it."I know you're just pulling my leg when you say you can fly."
leg
your leg