sul·fu·re·ous adjective orsul·phu·re·ous\|səl|fyu̇rēəs\ Etymology: Latin sulfureus, sulphureus, from sulfur, sulphur, sulpur sulfur + -eus -eous : consisting of sulfur : having the qualities of sulfur especially when burning : impregnated with sulfur : sulfur-colored : sulfurous • sul·fu·re·ous·lyadverb • sul·fu·re·ous·nessnoun-es