A type of market order that is canceled and re-submitted as a limit order if the price of the asset moves dramatically after the investor places the order. The limit on the limit order is placed at around the current market price as determined by a broker. This type of order adds a protective measure, helping the investor ensure his or her market order will not be completed at a price that is far off from the market price at the time of the order.
Taobiz explains Market-With-Protection Order
For example, say you place a market-with-protection order to sell 1,000 shares at the current market price of $45. If half of the order is filled at this price but the price of the shares start to fall rapidly to $35, the original market order is canceled and a limit order is placed for the remaining shares at $40. If the price climbs back to $40, the rest of the shares will be sold. If there was no protection on the order, the shares may have been sold at $35, which is far off from the market price of $45 that the investor originally wanted.