term:

Fungible

fungible adj

[New Latin fungibilis, from Latin fungi to perform]
: being something (as money or a commodity) one part or quantity of which can be substituted for another of equal value in paying a debt or settling an account [oil, wheat, and lumber are commodities]
n : something that is fungible

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.