Trapo is the common Spanish word for “cloth” or, more commonly, “rag”.
It sounds nothing like the similar words in English, except… it turns out to be a close cousin of drape & drapery.
All come from the same old Irish word, drapih, meaning, “garment.”
We can see the parallel in the t-r-p and d-r-p mapping. Both are the same roots except for the t/d shift, which is a very common and not-noteworthy transition.
A drape, after all, is a form of cloth.