filler cap 
noun
A cap closing the pipe leading to the petrol tank of a motor vehicle.On the outside, all it lacks is a pair of running boards - chrome is again used to stunning effect on the wheels, door handles, filler cap and exhaust tail pipe, while bumpers and side mouldings are body-coloured....
- The petrol filler cap was smashed on arrival, so I've emailed the vendor to see if a replacement can be provided.
- Inside the boot is the lever for opening the fuel filler cap.
- price war
- pricey
- price–earnings multiple
- price–earnings ratio
- Prichard
- priciness
- pricing power
- prick
- prick-bill
- prick ear
- prick-eared
- pricked-out
- pricker
- pricket
- pricket candlestick
- prick farrier
- pricking iron
- pricking out
- pricking-up
- pricking-wheel
- prickle
- prickle-apple
- prickleback
- prickle cell
- pricklefish