roughage(n = noun.food) fiber - coarse, indigestible plant food low in nutrients; its bulk stimulates intestinal peristalsis; Array
is a kind of food product, foodstuff
has particulars: bran

roughage, n.
1 coarse material with a high fibre content, the part of food which stimulates digestion.
2 coarse fodder.

Etymology:
ROUGH + -AGE 3