The term 'Added Onto' can be summarized by two crossword solutions: 'SUPPLEMENTED' (12 letters) and 'ANNEXED' (7 letters). SUPPLEMENTED means to add something to an existing thing in order to make it more complete or to increase its size. ANNEXED is similar, but it usually refers to the addition of a physical space or territory. Both words imply that something has been added to an existing thing, making it larger or more complete.