gypsum:  The word gypsum originated among the Semitic languages, with a relative or ancestor of Arabic jibs and Hebrew gephes ‘plaster’. Greek adopted this unknown form as gúpsos, which passed into Latin as gypsum. (An Italian descendant of gypsum is gesso ‘plaster’, borrowed by English in the 16th century for ‘plaster as a surface for painting on’.) => gesso
substance (hydrated calcium sulphate) used in making plaster, late 14c., from Latin gypsum, from Greek gypsos "chalk," according to Klein, a word perhaps of Semitic origin (compare Arabic jibs, Hebrew gephes "plaster").