Diamond turn

If a driver approaches a four-way intersection and wishes to make a turn opposite of their side of the road (e.g. a right turn if driving on the left side of the road, as in the UK or Australia), they should turn in a wide arc that passes close to the centre of the intersection.[1]

This is nowadays the standard type of driver's-side turning manoeuvre at a four-way intersection. In particular, at intersections with traffic lights, it enables a traffic signal phase to allow traffic approaching the intersection from two opposing directions to both turn right simultaneously without colliding.

The diamond turn is distinguished from a historically required manoeuvre wherein drivers simultaneously turning right from opposing directions were required to turn around a silent cop in the centre of the intersection, which resulted in the two vehicles looping past one another with their driver's sides adjacent.[1] This type of turn was eliminated, as it was unsuitable for intersections with traffic lights that used simultaneous right-turn green light phases for more than one approaching street.