convertible vs commutable

convertible is a noun but commutable is not a noun.

Word	Noun	Adjective	Verb	Adverb
convertible	Yes	Yes	No	No
commutable	No	Yes	No	No

convertible (noun)	commutable (noun)
a car that has top that can be folded or removed
a sofa that can be converted into a bed
a corporate security (usually bonds or preferred stock) that can be exchanged for another form of security (usually common stock)

convertible (adjective)	commutable (adjective)
capable of being exchanged for or replaced by something of equal value	subject to alteration or change
designed to be changed from one use or form to another	capable of being exchanged for another or for something else that is equivalent
capable of being changed in substance as if by alchemy