O / orchēstra
noun greek

orchēstra

gen. orchēstrae · gender feminine · decl. 1st
= ὀρχήστρα.
The place where the Senate sat; the orchestra
The place where the Senate sat in the theatre, the orchestra: in orchestrā senatorum sunt sedibus loca destinata, Vitr. 5, 6; Juv. 7, 47; Suet. Caes. 39; id. Aug. 35; 44; id. Claud. 21 et saep.—
the Senate by extension
Transf., the Senate (poet.): similesque videbis Orchestram et populum, Juv. 3, 178.—
Another place on the stage
Another place on the stage, acc. to Fest. p. 181 b; cf. Müll. ad h. l.