Its a "colloquial" way of referring to a prostitute (or person acting as such) in the area of Rome. Very often spelled as sorca, but sorcia is also understood to have the same meaning.
"sorcio" is a synonym (Centre Italy dialectal version, but understandable everywhere) for mouse (topo, in standard Italian), "sorcia" is the feminine and the feminine of mouse is often used (in the various dialectal versions) to refer to prostitutes or (as a proxy) to "easy women" (the latter meaning is, fortunately, slowly disappearing from the culture).