(Teobaldo Visconti) c1210–76, Italian ecclesiastic: pope 1271–76.
- Gregory XI
noun 1. (Pierre Roger de Beaufort) 1330–78, French ecclesiastic: pope 1370–78.
- Gregory XIII
noun 1. (Ugo Buoncompagni) 1502–85, Italian ecclesiastic: pope 1572–85, educator and innovator of the modern calendar. noun 1. 1502–85, pope (1572–85). He promoted the Counter-Reformation and founded seminaries. His reformed (Gregorian) calendar was issued in 1582
- Gregory XIV
noun 1. (Niccolò Sfandrati) 1535–91, Italian ecclesiastic: pope 1590–91.
noun 1. Foundry. the tensile strength of greensand. 2. Metallurgy. the tensile strength of an unsintered compact.