tap / space
Classic usage
Pronunciation: /pəˈtɹoʊliəm/
Reading level: hard
Estimated CEFR level: C2 — Proficiency
Estimated from word frequency; not an official CEFR classification.
Learned borrowing from Medieval Latin petroleum. Doublet of petrol.
crude oil, crude, rock oil, fossil oil, oil
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tap / space
Classic usage
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