The term 'Tree Topper' is a job description for an object that is placed at the top of a Christmas tree. The crossword solutions for this term are 'STAR', which is a four letter word. A Tree Topper is typically a STAR-shaped ornament that is placed at the very top of a Christmas tree to give it a festive look. It is usually the last decoration to be added to the tree and is often the most eye-catching.