Synonyms for Scummy (same or very similar meaning)
WordNet sense 1 (of the most contemptible kind):
abject, low, miserable, scurvy, low-down
WordNet sense 2 (deserving of contempt or scorn):
contemptible
WordNet sense 3 (soiled or likely to soil with dirt or grime):
dirty, unclean, soiled
From the ODE community, based on WordNet
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