About 0.01 uses per million words.
A scourer may be in the form of a mesh (ball) of wires, a flat piece of a rough fabric, or a pad with a soft sponge-like side and a more abrasive side.
scowrer scouring powder scourer pad deckscrub pot scrubber scouring pad pot scrubber brush scrub scraper scrubber
and of for
scour scoured scourers scouring scours