unleaded petrol
Học thuậtThân thiện
Definition
Noun: - Gasoline that has not been treated with a lead compound: Unleaded petrol is a type of motor fuel that does not contain added tetraethyl lead, which was historically used to boost octane ratings and prevent engine knocking. Its use became widespread to reduce harmful lead emissions.
Usage
Unleaded petrol is the standard fuel for most modern vehicles. It is specified by its octane rating (e.g., 87, 91, 95). Using leaded petrol in a vehicle designed for unleaded fuel can damage its catalytic converter and emission control systems. - Most cars on the road today require unleaded petrol. - The price of unleaded petrol has increased this week.
Advanced Usage
- Technical Specification: Often referred to by its Research Octane Number (RON), e.g., "95 RON unleaded".
- Environmental Context: The phase-out of leaded petrol is considered a major public health achievement due to the reduction in airborne lead pollution.
Variants and Related Words
- Unleaded (adj): Describing fuel without lead additives. Can be used independently (e.g., "Fill it up with unleaded, please.").
- Premium Unleaded: A higher-octane grade of unleaded petrol.
- Leaded Petrol (n): The antonym; gasoline treated with lead compounds, now largely obsolete.
Synonyms
- Unleaded gasoline (primarily US English)
- Petrol (general term, but context specifies unleaded)
Related Phrases
- To run on unleaded: Describes a vehicle's fuel requirement.
- This model runs on unleaded.
- Unleaded only: A warning or instruction found on fuel caps or in vehicle manuals.
- The fuel cap clearly states "unleaded only".
Noun
- gasoline that has not been treated with a lead compound