orchestra āļāļ·āļāļāļ°āđāļĢ orchestra āļāļ·āļāļāļ°āđāļĢ Music A large group of musicians who play together on various instruments, usually including strings, woodwinds, brass instruments, and percussion instruments.Music The instruments played by such a group.The area in a theater or concert hall where the musicians sit, immediately in front of and below the stage.The front section of seats nearest the stage in a theater.The entire main floor of a theater.A semicircular space in front of the stage used by the chorus in ancient Greek theaters.