WordNet sense 1 (lacking originality or spontaneity; no longer new):

moth-eaten, stale

WordNet sense 2 (not original; not being or productive of something fresh and unusual):

unoriginal

WordNet sense 3 (covered with a layer of dust):

dust-covered

WordNet sense 4 (soiled or likely to soil with dirt or grime):

dirty, unclean, soiled