The term 'ROSE SUPPORTER' can be broken down into two crossword solutions: STEM (4 letters). The word 'STEM' is defined as the main stalk of a plant, which supports the leaves, flowers, and fruit. In this context, a rose supporter would be someone who provides support for roses, such as providing nutrients, water, and protection from pests and diseases. This could include gardeners, florists, and other professionals who work with roses.