Stupendous rhymes with:
horrendous, tremendous, candace, hondas, horrendous, indus, jaundice, landess, tremendous, addidas, addidas', adidas, aldous, brajdas, broadus, candace, constantinides, cowardice, delgiudice, enterividous, exodus, geddes, georgiades, goddess, gradus, hazardous, hondas, horrendous, indus, jaundice, judas, landess, logiudice, madis, midas, modus, pardus, redus, rhodus, sardas, sodus, stewardess, tremendous