Grist /(?)/

Grist

n.
  1. Ground corn; that which is ground at one time; as much grain as is carried to the mill at one time, or the meal it produces.
    Get grist to the mill to have plenty in store.
    — Tusser. Q.
  2. Supply; provision.
  3. In rope making, a given size of rope, common grist being a rope three inches in circumference, with twenty yarns in each of the three strands.

Phrases & Compounds

All is grist that comes to his mill
all that he has anything to do with is a source of profit.
To bring grist to the maill
to bring profitable business into one's hands; to be a source of profit.