An order to a broker in which the client instructs the a broker to execute only part of the order if necessary. This situation usually arises when the broker cannot find a corresponding order. For example, if an investor makes an order to a broker to sell 1000 shares at a certain price but there are only buyers for 600 shares, the broker partially executes the order and looks for buyers for the remaining 400. The leftovers from an any-part-of order are called leaves. This order contrasts with an all-or-none order.