rhetoric vs fustian

rhetoric and fustian both are nouns.

Word	Noun	Adjective	Verb	Adverb
rhetoric	Yes	No	No	No
fustian	Yes	No	No	No

As nouns, fustian is a hyponym of rhetoric; that is, fustian is a word with a more specific, narrower meaning than rhetoric:

Other hyponyms of rhetoric include flourish, blah, bombast, claptrap, rant.

rhetoric (noun)	fustian (noun)
study of the technique and rules for using language effectively (especially in public speaking)	a strong cotton and linen fabric with a slight nap
using language effectively to please or persuade	pompous or pretentious talk or writing
high-flown style; excessive use of verbal ornamentation
loud and confused and empty talk