Orchestra
In the early Greek theatre, the place occupied by the dancers and the chorus about the altar of Dionysos, the circular space reserved for the dancers and the chorus between the proscenium and auditorium.
orchēstra
In the early Roman theatre, a semicircular level space between the stage and the first semicircular rows of seats, reserved for the senators and other distinguished guests.
Latin borrowed from Greek orchestra ὀρχήστρα the dancing place. The orchestra was the primary performance space for the chorus in Greek theatre also adapted for use as an arena for Roman spectacle entertainment. The orchēstra was the space between the audience and the Greek skēnē or Roman scaenae possibly rectilinear in Early Classical Greek theatre circular in Classical Greek theatre horseshoe-shaped in Hellenistic theatre semicircular in Roman theatres.""