Orr is a popular surname in Scotland and Northern Ireland. Its origin is within the ancient kingdom of Dál Riata. The name may have a few origins, such as an Anglicisation of the name Ivar, or deriving from an Old English placename ora, or from the Gaelic odhar donn.

Orr is a fictional character in the classic novel Catch-22 by Joseph Heller. Orr is a bomber pilot in the squadron who is continually being shot down and having to crash land in the sea. Described as "a warm-hearted, simple-minded gnome", Orr is the only person in the Group considered to be crazier than his good friend Yossarian, with whom he shares a tent.

the Charonite Ferryman. Now dead.

Office of the Rail Regulator.

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Canadian hockey player (born 1948)

Oak Ridge Reservation

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