Istisna(redirected from Istisnah)
In Islamic law, a contract in which a buyer purchases an item for deferred delivery. The item must be described in detail and construction must fit the specifications. There is no set delivery date for the item. Usually, an istisna contract is made for specially made items. For example, one may make a contract to build a custom table for a client. Payment may be made in a lump sum or in installments.