divided highway

American  

noun

1. a superhighway with a broad median strip, designed to prevent collisions, headlight glare, etc., between vehicles moving in opposite directions, and usually having limited or cloverleaf access.

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divided highway British  

noun

1. Also called (in Britain and certain other countries): dual carriageway.  a road on which traffic travelling in opposite directions is separated by a central strip of turf, etc

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