Here's one definition: Naked short selling, or naked shorting, is the practice of selling a stock short, without first borrowing the shares or ensuring that the shares can be borrowed as is done in a conventional short sale. When the seller does not obtain the shares within the required time frame, the result is known as a "fail to deliver". However, the transaction generally remains open until the shares are acquired by the seller or the seller's broker, allowing a trade to occur when the order is filled.