A gemstone consisting of a quartz-like form of hydrated silica, typically semi-transparent and showing many small points of shifting colour against a pale or dark ground: a large opal [as modifier]: an opal ring
More example sentences
- The traditional kundan work has also been embellished with semi-precious and precious stones and beads such as tourmalines, tanzanites, opals, aquamarine and peridots.
- Diamonds and opals and onyx sat in lumps in the sparkling coloured windows.
- In a blinding flash the diamond, moonstone, opal, ruby and sapphire were molded together, inseparable, forever.
late 16th century: from French opale or Latin opalus, probably based on Sanskrit upala 'precious stone' (having been first brought from India).