OPAL
WordNet
noun
(1) A translucent mineral consisting of hydrated silica of variable color; some varieties are used as gemstones
WiktionaryText
Etymology
In Florio's A World of Words 1598 as opale, from French opale or opalle, from Latin opalus, probably from Greek ὀπάλλιος (opallios), maybe from Sanskrit upala-s "gem" or "opal".
Noun
- A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity, of the chemical formula SiO2·nH2O.
- , , A colloquial name used in molecular biology referring to a particular stop codon sequence, "UGA."