light bread vs breadstuff

light bread and breadstuff both are nouns.

Word	Noun	Adjective	Verb	Adverb
light bread	Yes	No	No	No
breadstuff	Yes	No	No	No

As nouns, breadstuff is a hypernym of light bread; that is, breadstuff is a word with a broader meaning than light bread:

light bread: bread made with finely ground and usually bleached wheat flour
breadstuff: food made from dough of flour or meal and usually raised with yeast or baking powder and then baked

Other hypernyms of light bread include bread, staff of life.

light bread (noun)	breadstuff (noun)
bread made with finely ground and usually bleached wheat flour	food made from dough of flour or meal and usually raised with yeast or baking powder and then baked
	flour or meal or grain used in baking bread