[{"Bold_text": "noun", "List Items": ["Mineralogy.a variety of chalcedony having straight parallel bands of alternating colors.Compare Mexican onyx Mexican onyx.", "(not used technically) an unbanded chalcedony dyed for ornamental purposes.", "black, especially a pure or jet black:The pelt of this animal can range from onyx to light brown, depending on the season.", "Medicine/Medical.a nail of a finger or toe."]}, {"Bold_text": "adjective", "List Items": ["made of or set with banded chalcedony:He wore the onyx cufflinks she had given him for his birthday.", "black, especially jet black:She was a vision in black, from her onyx hair to her shiny boots."]}]