Origin of pumiceMiddle English pomis from Old French from Classical Latin pumex from Indo-European base an unverified form (s)poimno-, foam
transitive verb-·iced, -·ic·ing
transitive verbpum·iced, pum·ic·ing, pum·ic·es
Origin of pumiceMiddle English from Anglo-Norman pomis from Late Latin pōmex from Latin pūmex alteration of spūma foam
(third-person singular simple present pumices, present participle pumicing, simple past and past participle pumiced)
From Latin pÅ«mex (“pumice stone").