fun·gi·ble 
(fŭnjə-bəl)
(fŭnjə-bəl)adj.
1. Law Returnable or negotiable in kind or by substitution, as a quantity of grain for an equal amount of the same kind of grain.
2. Interchangeable.
n.
often fungibles Law Something that is fungible.
[Medieval Latin fungibilis, from Latin fungī (vice), to perform (in place of).]
fun′gi·bili·ty n.