orchestra

Etymology

Borrowed from Latin orchēstra, itself a borrowing from Ancient Greek ὀρχήστρα (orkhḗstra) (a derivative of ὀρχέομαι (orkhéomai, “to dance”)).

noun

1. (music) A large group of musicians who play together on various instruments, usually including some from strings, woodwind, brass and/or percussion; the instruments played by such a group.
   It requires quite an orchestra to get a train to start; the guard blows his horn, the stationmaster rings a large bell, and the engine whistles. 1941 February, Voyageur, “The Railways of Greece”, in Railway Magazine, page 67
2. A semicircular space in front of the stage used by the chorus in Ancient Greek and Hellenistic theatres.
3. The area in a theatre or concert hall where the musicians sit, immediately in front of and below the stage, sometimes (also) used by other performers.