(noun) a translucent mineral consisting of hydrated silica of variable color; some varieties are used as gemstones

Source: WordNet® 3.1



opal (plural opals)

(mineral) A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity, of the chemical formula SiO2ยทnH2O.

(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.


• OLAP, POLA, Palo, alop, aplo-, pola

Proper noun


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.[Developed 2005.]

A hamlet in Alberta, Canada

A census-designated place in Virginia

A town in Wyoming


• OLAP, POLA, Palo, alop, aplo-, pola

Source: Wiktionary

O"pal, n. Etym: [L. opalus: cf. Gr. upala a rock, stone, precious stone: cf. F. opale.] (Min.)

Definition: A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity.

Note: The precious opal presents a peculiar play of colors of delicate tints, and is highly esteemed as a gem. One kind, with a varied play of color in a reddish ground, is called the harlequin opal. The fire opal has colors like the red and yellow of flame. Common opal has a milky appearance. Menilite is a brown impure variety, occurring in concretions at Menilmontant, near Paris. Other varieties are cacholong, girasol, hyalite, and geyserite.

Source: Webster’s Unabridged Dictionary 1913 Edition


Word of the Day

7 October 2022


(noun) perennial herb of northeastern United States having a thick knotted yellow rootstock and large rounded leaves

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Coffee Trivia

Contrary to popular belief, coffee beans are not technically beans. They are referred to as such because of their resemblance to legumes. A coffee bean is a seed of the Coffea plant and the source for coffee. It is the pit inside the red or purple fruit, often referred to as a cherry. Just like ordinary cherries, the coffee fruit is also a so-called stone fruit.

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