Formula 1 has a vocabulary all its own, and broadcasters rarely stop to explain it. This glossary covers the terms you are most likely to hear on race day, in alphabetical order, in plain English. For deeper explanations, most entries link to our full guides.

A to D

ADUO
The 2026 in-season engine upgrade allowance that lets manufacturers behind the benchmark bring defined power unit improvements during the year. See how the 2026 power units work.
Apex
The innermost point of a corner, where the car is closest to the inside kerb. “Missing the apex” means running wide.
Backmarker
A car near the back of the field, usually one about to be lapped by the leaders.
Blistering
Tyre damage caused by overheating, where bubbles form beneath the surface and burst. See tyres explained.
Blue flag
The signal telling a slower car to let a lapping car through. See flags explained.
Box, box
The radio instruction to pit this lap. From the German Boxenstopp; chosen because it is unmistakable over radio.
Chicane
A tight sequence of corners, often added to slow cars on a fast section of track.
Clean air
Undisturbed air ahead of a car with nothing in front of it. Cars are fastest in clean air.
Compound
The hardness of a tyre’s rubber, from C1 (hardest) to C6 (softest).
Constructor
A team, in the sense that it builds its own chassis. The constructors’ championship is the team title.
Cost cap
The annual limit on team spending. See the cost cap explained.
Deg
Short for degradation: the rate at which a tyre loses performance, measured in tenths per lap.
Delta
A time difference — between a lap and a target, between two drivers, or against the minimum time under a safety car.
Dirty air
The turbulent wake behind a car, which reduces a following car’s downforce. See aerodynamics explained.
Double-stack
Pitting both of a team’s cars one immediately after the other.
Downforce
The aerodynamic force pressing the car onto the track, which multiplies grip.
Drive-through
A penalty requiring the driver to drive through the pit lane at the speed limit without stopping. See penalties explained.

E to L

Energy store
The battery in the hybrid power unit.
Flat spot
A patch of tyre worn flat by locking the wheel under braking, causing vibration.
Flying lap
A timed lap at full speed, as opposed to an out-lap or in-lap.
Formation lap
The lap before the start when cars leave the grid, warm their tyres and return to their grid slots.
Graining
Tyre damage where cold rubber tears and rolls into ridges on the surface, reducing grip.
Grid penalty
A drop in starting position, applied for engine changes or driving offences.
Ground effect
Generating downforce with the car’s floor rather than its wings.
Halo
The titanium hoop above the cockpit that protects the driver’s head.
Harvesting
Recovering energy into the battery, mostly under braking.
In-lap
The lap returning to the pits after a flying lap or at the end of a stint.
Intermediates
Green-marked tyres for damp conditions.
Lift and coast
Lifting off the throttle before the braking zone to save fuel, tyres or brakes, or to harvest energy.
Lock-up
When a wheel stops rotating under braking and the tyre skids, often producing a flat spot.

M to P

Marbles
Fragments of rubber shed by tyres that collect off the racing line and are slippery to drive on.
Marshals
The volunteers stationed around the circuit who wave flags and recover cars.
MGU-K
The electric motor-generator on the crankshaft, tripled in power for 2026.
Out-lap
The lap leaving the pits, used to warm tyres before a flying lap.
Overcut
Staying out longer than a rival who has pitted to gain track position. See strategy explained.
Overtake Mode
The driver-activated electrical boost that replaced DRS in 2026. See what is Overtake Mode.
Oversteer
When the rear of the car loses grip before the front, making the car turn more than the driver intended.
Paddock
The area behind the pits where teams’ motorhomes and hospitality units are based.
Parc fermé
The rules that lock a car’s set-up between qualifying and the race. See parc fermé explained.
Pit wall
The stand on the pit straight where the team principal, strategists and engineers sit during sessions.
Plank
The wooden board under the car whose wear enforces ride-height rules.
Pole position
The first place on the grid, awarded to the fastest qualifier. See qualifying explained.
Porpoising
Violent bouncing caused by the floor’s airflow stalling and reattaching at high speed.
Purple sector
The fastest sector time of the session, shown in purple on timing screens. Green is a personal best; yellow is slower than the driver’s best.

Q to Z

Q1, Q2, Q3
The three knockout qualifying sessions.
Racing line
The fastest path through a corner, which becomes rubbered-in and grippier over a weekend.
Red flag
The signal stopping a session. See red flag rules.
Safety car
The road car that leads the field at reduced speed while a hazard is cleared, bunching the pack.
Sector
One of three timed segments of each lap.
Slipstream
The low-drag pocket of air behind a car, which lets a following car go faster on a straight — the “tow”.
Sprint
The short Saturday race held at six 2026 rounds. See sprint format explained.
Stint
The laps completed on one set of tyres between pit stops.
Stewards
The officials who investigate incidents and issue penalties.
Super licence
The FIA licence required to race in F1. See how to become an F1 driver.
Team orders
Instructions from a team to its drivers about their running order. See team orders explained.
Telemetry
Live data transmitted from the car to the pit wall — speed, throttle, brakes, temperatures and hundreds of other channels.
Tow
See slipstream.
Track limits
The white lines defining the circuit; laps are deleted for running all four wheels beyond them.
Undercut
Pitting before a rival to gain position with fresh tyres.
Understeer
When the front loses grip before the rear, so the car turns less than the driver intended.
Virtual safety car (VSC)
A race neutralisation that slows all cars to a delta time without deploying a physical safety car. See the VSC explained.
Wets
Blue-marked tyres for heavy rain.

Frequently asked questions

What does “box box” mean?

The radio call to pit this lap, from the German word for pit garage.

What is a purple sector?

The fastest sector time anyone has set in the session, shown in purple on the timing screen.

What does “delta” mean?

The time difference between two things, such as a driver’s current lap and a target time.

What are marbles?

Fragments of tyre rubber that collect off the racing line and are slippery to drive on.