Fill Or Kill (FOK) An order to fill a transaction immediately and completely or not at all. Investopedia Says: This type of order is usually for a large quantity of stock, and must be filled in its entirety or canceled (killed). Examples include market and limit orders requiring immediate execution. In reality, the fill-or-kill type of trade does not occur very often. Related Terms: Canceled Order Fill Immediate Or Cancel Order - IOC Kill Limit Order Market Order Stop Limit Order Stop Limit Order Time In Force |