A viscous liquid, consisting chiefly of a mixture of hydrocarbons and varying in colour from black or dark brown to light yellow, that is formed by…

Rock. Only in oil of petre n. also petre oil petroleum.

= petroleum, n. In early use also †oil (of) petrol. Cf. sense 3. Obsolete.

any of various green-coloured oils, esp. (a) oil pressed from unripe olives; (b) U.S. regional = petroleum, n. (now rare); (c) = anthracene oil n. at…

oil of saltpetre: petroleum. spirits of saltpetre: nitric acid. Obsolete.

Petroleum; (also) a distillation product of petroleum, esp. one used as a lubricant, moisturizer, or laxative.

(originally) oil or naphtha obtained from coal; (in later use) (North American) oil refined from petroleum, shale, etc.; kerosene; petroleum…