noun

• (mineralogy) A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity, of the chemical formula SiO₂·nH₂O.
• (gemology) A precious gem, an iridescent gemstone found in the opal-silica mineral substrate (potch)
• (biology, genetics, biochemistry) A colloquial name used in molecular biology referring to a particular stop codon sequence, "UGA."
• Any of various lycaenid butterflies of the genus Nesolycaena.
• A female given name from English from the precious stone, invented in the nineteenth century.
• (Australia) A type of petrol made by British Petroleum designed to be unable to be used for petrol sniffing.
• A hamlet in Alberta, Canada
• A census-designated place in Virginia
• A town in Wyoming