What is Derived Demand (this is an economics question)

Derived demand is a term used in the economic analysis that describes the demand placed on one good or service as a result of changes in the price for some other related good or service. It is a demand for some physical or intangible thing where a market exists for both related goods and services in question.

Derived Demand a need or want for a service, commodity, etc ..., That is a consequence of the demand for something else.