Horrendous rhymes with:
stupendous, tremendous, candace, hondas, indus, jaundice, landess, stupendous, tremendous, addidas, addidas', adidas, aldous, brajdas, broadus, candace, constantinides, cowardice, delgiudice, enterividous, exodus, geddes, georgiades, goddess, gradus, hazardous, hondas, indus, jaundice, judas, landess, logiudice, madis, midas, modus, pardus, redus, rhodus, sardas, sodus, stewardess, stupendous, tremendous
Horrendous sounds like:
harmetz, hermitage, hermits, hernandes, hernandez, hernandez's, herniates, hormats, hornet's, hornets