WordNet sense 1 (suggestive of or tending to moral looseness):

lewd, obscene, salacious

WordNet sense 2 ((of behavior or especially language) characterized by obscenity or indecency):

dirty

WordNet sense 3 (thickly covered with ingrained dirt or soot):

dingy, grimy, grubby, grungy, begrimed, dingy

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

unclean, soiled