Verb
(UK) (intransitive, or transitive with of) To have an insufficient amount (of).
My parents were very poor, and we often went short of food.
(finance) To sell a financial product (such as a share) now, even though one does not presently own it, in the hope of buying it more cheaply for delivery at a later date, so as to profit from a fall in price below the price at which one sold it; cf. go long.
Source: en.wiktionary.org