Corundum(n.) The earth alumina, as found native in a crystalline state, including sapphire, which is the fine blue variety; the oriental ruby, or red sapphire; the oriental amethyst, or purple sapphire; and adamantine spar, the hair-brown variety. It is the hardest substance found native, next to the diamond.
Thesaurus Entries
ablation, ablative, abradant, abrasion, aluminum oxide, attrition, attritive, auto polish, buffing, burnish, burnishing, chafe, chafing, colcothar, corundum, crocus, detrition, dressing, emery, emery board, emery paper, erasure, erosion, erosive, file, filing, fretting, galling, garnet, gnawing, grazing, grinding, lawn-roller, limation, nail file, polish, polishes, polishing, pumice, pumice stone, rasp, rasping, roller, rottenstone, rouge, rubbing away, sandblasting, sanding, sandpaper, scouring, scrape, scraping, scratch, scratching, scrub, scrubbing, scuff, shining, shoe polish, silicon carbide, silver polish, sleeker, slicker, smooth, smoother, smoothing, wax, wear, wearing away