from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A xystus.
from the GNU version of the Collaborative International Dictionary of English
- n. A long and open portico, for athletic exercises, as wrestling, running, etc., for use in winter or in stormy weather.
from The Century Dictionary and Cyclopedia
- n. In ancient architecture, a covered portico or open court, of great length in proportion to its width, in which athletes performed their exercises; or, in Roman villas, sometimes, a garden walk planted with trees. Also xystos, xystus.
Sorry, no etymologies found.
If you've never heard of an ancient portico whose name is pronounced ZIST, the spelling xyst may well elude you.