A UK university offering distance learning taught courses to people without formal academic qualifications, teaching being by correspondence and online with mostly optional tutorials and for some courses compulsory summer schools. Access to postgraduate research is selective and is primarily taught on campus using traditional methods.

completely open / having no laws or law enforcement / unsettled or unresolved / vulnerable or unprotected / (sports) without the presence of opponents nearby

Of or pertaining to work that is done from home, especially via the Internet.

The collaborative design of things, especially of open source software, through use of publicly shared design information.

(business, finance) A trading method whereby traders gather in person, often in a pit, and call out to all their desire to buy or sell a quantity at a given price, transactions being consummated when two parties can agree on a price. Most frequently used in securities markets.

(finance) The total number of contracts outstanding between market participants in a market for futures, options, or other derivatives.

(computing) A proxy server that may be accessed by any Internet user.

A music, poetry, or comedy stage platform with open invitation, that is, where anyone is invited to perform.

An uncovered fire.

(idiomatic) To begin firing (weapons) at something or someone.