An order (market order) that represents an instruction to a broker to sell a certain number of tradable securities (shares, bonds, etc.) Market sell order will execute on the best available bid price. A market order generally will execute (be filled) at or near the current bid for a sell order.

An investor with holds of securities can instruct its broker to sell at the market as per certain conditions.

A limit sell order could execute for more than a set limit price.