The term "backing" can refer to several different meanings depending on the context in which it is used.
1) In music, backing refers to the accompanying instrumental track that supports a singer or vocalist during a performance. It includes all of the instruments and vocals other than the lead melody.
2) In sports, backing can refer to supporting an athlete by providing them with resources such as training facilities, equipment, coaching, etc., in order for them to achieve their full potential.
3) In finance, backing refers to providing financial support or investment capital to a project, business venture, or individual. It is the act of lending money or extending credit to someone in exchange for interest or other compensation.