def

fuelOil

Petroleum based oil burned for energy

meta

supertypes

marker

Marker labels a dict with typing information

    phenomenon

Aspect of scientific interest with measurable quantities

        substance

Matter in one the three states solid, liquid, or gas

            fluid

Liquid or gas

                liquid

Substance with definite volume but takes the shape of its container

usedBy

boiler-oilHeating

Heating by the combustion of fuel oil

oilHeating

Heating by the combustion of fuel oil