xystusEnglishOxford Dictionary of Englishxystus /ˈzɪstəs / ▸ noun (plural xysti /ˈzɪstʌɪ/) 1 (in ancient Greece) a long portico used by athletes for exercise. 2 (in ancient Rome) a garden walk or terrace. – ORIGIN Latin, from Greek xustos ‘smooth’, from xuein ‘to scrape’.