unleaded

UK/ˌʌnˈlɛd.əd/

nounB1+Occasional — familiar, but not everyday · #11,646 of 15,258neutral

Unleaded is petrol made without any lead in it. Fill up with unleaded, unleaded only, premium unleaded.

Lead was added from the 1920s to stop engines knocking, and removing it was one of the great public health victories of the century: children's blood lead levels fell sharply everywhere it was banned. Almost no country still sells the leaded kind.

Definitions of unleaded

1noununleadedPetrol made without any lead in it.B1+
“The car only takes unleaded, so don't fill it with diesel.”

unleaded is a fuel.

Where it comes from

Un- plus leaded. The word appeared in the 1970s as leaded petrol began to be phased out.

From un + leaded. The US standard of identity comes from 40 CFR §79.32.

Etymology from Wiktionary, CC BY-SA

Practised in Vehicles & Machines

Practise this word

unleaded in the wild

Initially marketed as a supplement for use in leaded gasoline, MMT was later used in unleaded gasoline to increase the octane rating.
Methylcyclopentadienyl manganese tricarbonyl
Typical unleaded petrol contains 25% aromatics, such as toluene, ortho-xylene and para-xylene.
Opal (fuel)
Grupa Lotos was a producer of unleaded gasoline, diesel, fuel oils, aviation fuels, motor and industrial lubricants, bitumens and waxes.
Grupa Lotos
Sinfelt was an American chemical engineer whose research on catalytic reforming helped lead to the introduction of unleaded gasoline.
John H. Sinfelt

From Wikipedia, CC BY-SA 4.0. These sentences were written by other people about their own subjects; they are here to show the word at work, not as anybody’s opinion.

← Vocabulary