advantageous vs expedient

advantageous is not a noun while expedient is a noun.

Word	Noun	Adjective	Verb	Adverb
advantageous	No	Yes	No	No
expedient	Yes	Yes	No	No

advantageous (noun)	expedient (noun)
	a means to an end; not necessarily a principled or ethical one

advantageous (adjective)	expedient (adjective)
giving an advantage	serving to promote your interest
appropriate for achieving a particular end; implies a lack of concern for fairness	appropriate to a purpose; practical