petroleum

petroleum — noun

1. natural oil brought up from deep rock layers or seabeds and refined into fuels s

1.nounB2
Definition

natural oil brought up from deep rock layers or seabeds and refined into fuels such as petrol and diesel.

Example

The company found petroleum under the desert after months of drilling.

find petroleum under [place]

Petroleum was discovered near the fishing town in 1984.

passive: petroleum was discovered

Common collocations
  • petroleum reserves
  • petroleum products
  • petroleum pipeline
  • petroleum spill
Synonyms
  • oil

    the everyday broad word; context may also mean cooking oil, motor oil, or fuel oil.

  • crude oil

    the usual industry term when you want to stress that it has not been refined yet.

Usage Note

Usually uncountable and most common in technical, business, and news writing. In everyday speech, people often say crude oil or simply oil, while petroleum is the more formal name for the raw substance before refining.

Common Mistakes

My car runs on petroleum.
My car runs on petrol.
petroleum names the raw substance or a technical category; everyday car fuel is usually called petrol or gasoline.

Word family

  • petrol
    nounA2
  • petrochemical
    adjectiveC1
  • petrochemical
    nounC1

Synonym discussion

Sense: noun/1

Petroleum is the formal technical word for oil as it comes from underground before it is separated into different products. Oil is the everyday word, but it is much broader: it can mean petroleum, engine oil, or cooking oil, so learners must read the context carefully. Crude oil is the closest practical synonym and is often the preferred term in industry when the liquid has not yet been refined. Mineral oil can overlap in technical writing, but in daily English it often refers to a clearer refined oil used in cosmetics or medicine, so it is not always a safe substitute. A news report may say petroleum exports, but an everyday conversation usually says oil.

oil ↗crude oilmineral oil

Common collocations

Nouns

  • petroleum industry
  • petroleum products
  • petroleum reserves

Phrases

  • drill for petroleum
  • discover petroleum
  • refine petroleum

Etymology

GreekLatinMedieval LatinEnglish

Petroleum came into English through medieval Latin. The word joins Greek petra, meaning "rock", with Latin oleum, meaning "oil", so its basic idea is "rock oil". It was used for the natural oil found in the earth.