call and response

A style found in almost all types of music, from tribal to classical to folk to jazz to rock to rap. The melody is split between two different instruments or sections, each playing a brief snippet, so that it seems like one instrument is echoing or responding to the other.

A good example is found in the chorus of the Rap song O.P.P.:

Lead Singer:You down with O.P.P?
Backup singersYeah, you know me!!

American Black Gospel music had/has a lot of this. In the development of Jazz from various influences, (including this), call and response became a major characteristic. Louis Armstrong and the King Oliver Creole Band in the 1920s really brought this out in the interplay between soloist and band. In Swing music this became a major feature. Brought almost to parody by the Glen Miller Orchestra.