gritstone

Từ điển WordNet v3.1 - WordNet Dictionary

noun

a hard coarse-grained siliceous sandstone
• Syn:
grit, gritrock
• Derivationally related forms:
gritty (for: grit), grit (for: grit)
• Hypernyms:
sandstone

• Từ đồng nghĩa / Synonyms:
  grit, gritrock