The term 'stage background' can be broken down into two parts: SCENERY and SET. SCENERY is a seven-letter word that refers to the physical environment of a stage, such as props, furniture, and other elements that help create the atmosphere of a play or performance. SET, on the other hand, is a three-letter word that refers to the arrangement of the SCENERY on the stage, which helps to create the desired effect for the audience. Together, these two words form the term 'stage background, ' which is used to describe the overall look and feel of a stage production.