The instrument or contract that would have existed by its own if the hybrid element (embedded derivative) was not made part of it. A host contract is the non-derivative component of any hybrid structure (a combined contract).

An example is a debt instrument that is embedded with a call option (callable bonds) or a put option (puttable bonds). Another example, is hybrid product like a gold-linked bond, where payment of coupon of the bond is pegged to the price of Gold. The coupon (interest payment) will increase or decrease in tandem with the price of gold in the market. The debt instrument/ the bond is  the non-derivative component, while interest payment is linked with a commodity that has an active price in the market (which is the derivative component). Gold is an embedded derivative in the sense that the host contract derives its value from gold, itself (i.e., changes in the market price of gold).