bran vs roughage

bran and roughage both are nouns.

Word	Noun	Adjective	Verb	Adverb
bran	Yes	No	No	No
roughage	Yes	No	No	No

As nouns, roughage is a hypernym of bran; that is, roughage is a word with a broader meaning than bran:

bran: food prepared from the husks of cereal grains
roughage: coarse, indigestible plant food low in nutrients; its bulk stimulates intestinal peristalsis

Other hypernyms of bran include fiber, fibre.

bran (noun)	roughage (noun)
food prepared from the husks of cereal grains	coarse, indigestible plant food low in nutrients; its bulk stimulates intestinal peristalsis
broken husks of the seeds of cereal grains that are separated from the flour by sifting