oleju

Oleju is the genitive singular form of the Polish noun olej, meaning oil. In Polish, oleju is used in phrases where the noun is in the genitive case, typically to indicate quantity, possession, or characteristics of the oil. Examples include butelka oleju (a bottle of oil), ilość oleju (the amount of oil), and smak oleju (the taste of the oil).

In everyday language, olej covers a wide range of substances designated as oils. Edible plant oils include olej rzepakowy (rapeseed oil), olej słonecznikowy (sunflower oil), and olej lniany (linseed or flaxseed oil). Olive oil is referred to as olej z oliwek. The term can also apply to non-edible or technical oils, such as olej mineralny (mineral oil) and olej silnikowy (engine oil), used in lubrication and industrial contexts.

Etymology traces the Polish olej to the Latin oleum, reflected in cognate terms in many European languages (for example, English oil, German Öl, French huile). The connection underscores a shared historical concept of a viscous, extractable fluid used for cooking, lighting, lubrication, and manufacturing.

See also: oil; list of common edible oils; industrial oils.