to sharpen; to hone; to wash (rice); to scour; to polish
tonoko; powder made from dried clay used as a polishing powder, filler material, etc.
scouring rushes; Equisetum hyemale; common horsetail
tonoko; powder made from dried clay used as a polishing powder, filler material, etc.
sludge from sharpening a sword, etc. on a grindstone