It's not clear. It could be a credit against your account with the retailer or it could be a credit on your credit card, if you used one to purchase something there. In the U.S. you would usually receive either a store credit or a refund. Combining the two is confusing to me.
A store credit means that you have a credit equal to the value of the item you returned but you must spend it at that store. A refund would be a credit against your credit card (backing out the original purchase) or usually a check if you paid by check or with cash.