A roundabout is a type of circular intersection or junction in which road traffic is slowed and flows almost continuously in one direction around a central island to several exits onto the various intersecting roads.The New Shorter Oxford English Dictionary, Volume 2, Clarendon Press, Oxford (1993), page 2632 In a modern roundabout, entering traffic must always yield to traffic already in the circle, and roundabouts have additional restrictions on the junction layout to give high safety.
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