To contrive and arrange mutually; construct or adjust, as a plan or system to be pursued, by conference or agreement.To plan; devise.In music, to arrange (a piece of music) for several voices or instruments.[From the noun concert.] To sing in concert.To act in concert: with with.n. Agreement of two or more in a design or plan; combination formed by mutual communication of opinions and views; accordance in a scheme or enterprise; harmony.n. In music: A set of instruments of the same kind, but of different sizes: as, a concert of viols. Also consort.n. A public performance of music in which several singers or instrumentalists, or both, participate; especially, one in which the program consists of detached numbers: also applied to the performance of an oratorio, but not of an opera.n. The harmonious combination of two or more voices or instruments.n. A concerto.