What is "hook turn"

n. A turn made by a vehicle across all lanes of traffic, sometimes used to improve the flow of through traffic or to keep the middle of the road free for trams etc.

A hook turn (also known as a perimeter-style turn in Canada) is a road cycling maneuver and traffic-control mechanism in which vehicles that would normally turn from the closest lane of an intersection instead turn from the farthest lane, across all other lanes of traffic.

Hook turns are commonly used by cyclists as a safer alternative to merging with motor vehicles, or having to cross multiple lanes of traffic to reach a turning lane.

The legal use of hook turns by motor vehicles is relatively rare, but has been implemented in some jurisdictions (notably Melbourne, Australia) to keep the center of a road free from congestion for use by trams or other services.