"pertaining to, resembling, or consisting of pumice," 1670s, from Latin pumiceus "of pumice stone," from pumex (see pumice). Pumicose (1811) also was used.
Entries linking to pumiceous
pumice n.
"type of volcanic rock having a loose or cellular structure," formerly used to smooth parchment or vellum, c. 1400, pomis, from Anglo-French and Old French pomis (13c.), from Late Latin pomicem (nominative pomex, genitive pumicis), from Oscan *poimex or some other dialectal variant of Latin pumex "pumice." This word is from PIE *(s)poi-mo-, a root with connotations of "foam, froth" (see foam (n.)), perhaps because pumice resembled a sort of fossilized foam.
With a wide variety of forms in Middle English, including pumish, pumey. Old English had pumic-stan. As a verb, "to polish or smooth with pumice," early 15c., from the noun.