ENGLISH
REFERENCE

petroleum

n.
US //pəˈtɹoʊɫiəm// UK //pətɹˈəʊliːəm// pe·tro·le·um
  1. 1 crude oil (n.)
    B2 Upper Intermediate Technical Science

    a thick, dark oil found under the ground that is used to make petrol and other fuels.

    a naturally occurring liquid mixture of hydrocarbons that is refined into various fuels and chemical products. Uncountable in its general sense, though countable when referring to specific types or grades.

    Example

    Many countries depend on petroleum to power their cars and factories.

    Example

    The extraction of petroleum from deep-sea reserves requires sophisticated engineering and carries significant environmental risks.

    Teacher's tip

    In everyday conversation, people usually just say 'oil' or 'crude oil'. 'Petroleum' is more common in scientific, industrial, or formal contexts.
    • crude oil
    • fossil fuel
    • oil
Origin

From Medieval Latin petroleum, from petra (“rock”) + oleum (“oil”). Doublet of petrol.

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