The word "wadded-up" is commonly used to describe something that has been crumpled or bunched up into a tight ball. There are a number of synonyms for this term that can be used to add variety and nuance to your writing. Some possible options include: crumpled, balled-up, compressed, squeezed, folded, tucked, twisted, mashed, bundled, and rumpled. Each of these synonyms conveys a slightly different sense of the way in which an object has been compressed or twisted. Experimenting with different word choices can help you convey your meaning more effectively, and keep your writing fresh and engaging.