Synonyms for Grubby (same or very similar meaning)
WordNet sense 1 (small sculpin of the coast of New England):
Myxocephalus aenaeusWordNet sense 2 (thickly covered with ingrained dirt or soot):
dingy, grimy, grungy, raunchy, begrimed, dingyWordNet sense 3 (soiled or likely to soil with dirt or grime):
dirty, unclean, soiledFrom the ODE community, based on WordNetadd/edit