Noun

1. A fine clay used in fulling cloth.

   • 1785, On Lord Sunderland's estate, in the county of Westmeath, there is a fine strata of fuller’s earth, a commodity of which our woollen manufacturers stand much in need: yet this bed lies unnoticed to all, except the peasantry on the soil. — The Times, 17 Oct 1785, p.3 col. D