To sell all of a product that is in stock. / (intransitive) To abandon or betray one's supporters or principles to seek profit or other personal advantage.

The final date on which a perishable product can be legally sold to the public. / (idiomatic, by extension) Used to indicate that something, or someone, is old and out of date.

To make a sale to a client who is not a lead but an unqualified prospect.

(Britain, finance) To sell misleadingly, fraudulently, or in violation of laws or regulations.

(commerce, finance) The practice of selling items or stock which one does not currently possess.

present participle of short sell

plural of sell-out

(intransitive, Britain, business) To become less by being sold. / (transitive, Britain, business) To reduce by selling.

(idiomatic) To betray a person; to conspire against someone for personal gain.

Alternative spelling of hard sell