dross

Từ điển WordNet v3.1 - WordNet Dictionary

noun

1. worthless or dangerous material that should be removed (Freq. 1)
- there were impurities in the water
• Syn:
impurity
• Derivationally related forms:
impure (for: impurity)
• Hypernyms:
waste, waste material, waste matter, waste product
2. the scum formed by oxidation at the surface of molten metals
• Syn:
slag, scoria
• Hypernyms:
scum
• Hyponyms:
basic slag

• Từ đồng nghĩa / Synonyms:
  slag, scoria, impurity