(computing) A system allowing hardware and software from different manufacturers to be used together seamlessly. / (physics) A system that can exchange both matter and energy with its surroundings.

A knifelike device with a blunt edge, used for slicing letters open.

(intransitive, cricket) To turn the face of the bat outwards in order to hit the ball on the off side.

Used other than figuratively or idiomatically: see open, attack: to begin attacking, to commence battle. / (cricket) Of a bowler: to bowl one of the first two overs.

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.

(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.

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

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

(film) Of a soft matte film, transferred to a home video format with the full frame exposed, thus having the theatrical mattes removed.