ξυσ-τός · xys-tos — LSJ
walking-place, walks
walking-place in the grounds of a private residence, X. Oec. 11.15 ; in a gymnasium, Plu. Sanit. 2.133d, OGI 764.42 (Pergam.) ; name of a gymnasium at Elis containing trees and racing-tracks, Paus. 6.23.1 ; open-air walks among trees and statuary, Vitr. 5.11.5 ; τὰ τῶν ξ. ἄλση Philostr. VA 8.26.
2 covered colonnade
covered colonnade in a gymnasium, for winter exercise, Vitr. l.c., Inscr.Délos l.c.
II meeting of athletes, clearing, clearing out
meeting of athletes from various places to compete in sports, ἀρχιερεὺς τοῦ σύμπαντος ξ. IG 14.1102, al., cf.5(1).669 (Sparta) ; opp. ξυστικὴ σύνοδος, Inscr.Olymp. 436. (Expld. by Paus. l.c. as a clearing, from the action of Heracles in clearing out (ἀναξύειν) the thorn-bushes from the ξ. at Elis ; perh. orig. ‘raked (ground)ʼ.)