Definitions from Wiktionary ( )

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

---

▸ Word origin

▸ Words similar to opal
▸ Usage examples for opal

▸ Idioms related to opal
▸ Wikipedia articles (New!)
▸ Popular adjectives describing opal
▸ Words that often appear near opal
▸ Rhymes of opal

▸ Invented words related to opal