Crude oil and Naphtha

Crude oil noun - A dark oil consisting mainly of hydrocarbons.

Naphtha and crude oil are semantically related in petroleum topic. In some cases you can use "Naphtha" instead a noun phrase "Crude oil".

Naphtha noun - Any of various volatile flammable liquid hydrocarbon mixtures; used chiefly as solvents.

Crude oil and naphtha are semantically related in oil topic. You can use "Crude oil" instead a noun "Naphtha", if it concerns topics such as petroleum.