slingshot
The act of passing cars queuing in the left-hand lane and using the right-hand lane to go around a roundabout, exiting at the desired junction having avoided the queue.
slingshot: roundabout queue-jumping via the inside lane
A slingshot is a driving maneuver at a roundabout where a vehicle enters the inside (right-hand) lane, passes stationary or slow-moving traffic in the outside (left-hand) lanes, then exits at the desired junction without waiting in queue. The term derives from the acceleration and trajectory effect: the driver uses the open space to sling themselves around and out of the traffic jam. This is a UK and European driving slang term, common in HGV, taxi, and courier work where time penalties for delay are direct financial losses.
The maneuver depends on specific roundabout geometry. It works on multi-lane roundabouts where the inside lane is not formally reserved for early exits, particularly those with three or four approach lanes and minimal lane markings specifying exit eligibility. Two-lane roundabouts offer little opportunity; single-lane roundabouts offer none. The driver must judge sight lines carefully: visibility around the curve of the roundabout determines whether oncoming traffic in the outside lanes can be spotted early enough to abort safely.
Legality and collision risk
A slingshot is not inherently illegal under UK law if the inside lane is open to traffic, but it sits in a grey zone. Police may treat it as careless or dangerous driving if sight lines are poor or if the driver cuts across lane markings aggressively. Insurance claims often hinge on whether the driver was within marked lane boundaries. The real hazard is conflict with vehicles already committed to inside-lane trajectories: a car exiting early from the inside lane may collide with a slingshot vehicle entering from behind at higher speed.
Professional drivers, particularly in courier and delivery sectors, perform slingshots as routine practice when traffic backs up at busy roundabouts during peak hours. Taxi drivers in congested urban areas use the tactic to improve turnaround times. The maneuver is less common in formal driver training, where defensive positioning and lane discipline are emphasized instead, but experienced drivers know the geometry of their regular roundabouts and exploit it.
The term is workplace slang and will not appear in official highway codes or driving instruction materials. Related terms include undertaking (the broader illegal practice of passing on the inside of a motorway) and filtering (the legal practice of moving between lanes in slow traffic on multi-lane roads), though slingshot is specific to roundabout behavior and emphasizes the speed and angle of the maneuver rather than cautious lane-changing.