Tozaigoe refers to shouts of 'tozai, tozai' (east west) from the backstage at the jobiraki (an opening) or before kojo (a ceremony to announce that an actor takes a new stage name) of kabuki (traditional drama performed by male actors) or ningyo joruri (traditional Japanese puppet theater).
東西声（とうざいごえ）は歌舞伎や人形浄瑠璃の序びらき、口上の前などに「東西、東西」と裏から声を掛けること。