BILL. Commercial transactions. A written statement of the terms of a contract, or specification of the items of a contract or of a demand. Also, a general name for any item of indebtedness, whether receivable or payable… Black’s 6th. Also, the creditor’s written statement of his claim, specifying the items. .. Black’s 1st. In Mercantile Law. The creditor’s written statement of his claim, specifying the items. It differs from an account stated in this, that a bill is the creditor’s statement; an account stated is a statement that has been assented to by both parties. Bouvier’s 8th.