Definitions

from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A mineral of hydrated silica.
  • noun A gemstone made of this mineral, noted for its rich iridescence.

from The Century Dictionary.

  • noun A mineral consisting of silica like quartz, but in a different condition, having a lower specific gravity and hardness and being without crystalline structure: it usually contains some water, mostly from 3 to 9 per cent. ; ; ; ; ; ; ;

from the GNU version of the Collaborative International Dictionary of English.

  • noun (Min.) A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • 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 biology , (genetics), (biochemistry) A colloquial name used in molecular biology referring to a particular stop codon sequence, "UGA."

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

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

Etymologies

from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English opalus, from Latin, alteration of Greek opallios, probably from Sanskrit upalaḥ, from variant of upara-, lower, from upa, below; see upo in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

In Florio’s A World of Words 1598 as opale, from French opale, from Latin opalus, from Byzantine Greek ὀπάλλιος (opallios), from Sanskrit उपल (upala, "gem”, “stone").

Support

Help support Wordnik (and make this page ad-free) by adopting the word opal.

Examples

  • Although opal is not a conclusive indicator of a wetter Mars, it does suggest some interesting scenarios.

    Archive 2008-11-16 Nicole 2008

  • The most durable opal is a solid piece, free from fractures.

    Mexican fire opals 2000

  • The most durable opal is a solid piece, free from fractures.

    Mexican fire opals 2000

  • The very word opal comes from the Sanskrit upala, meaning “precious,” which I guess says it all!

    Zolar’s Magick Of Color Simon 1994

  • The very word opal comes from the Sanskrit upala, meaning “precious,” which I guess says it all!

    Zolar’s Magick Of Color Simon 1994

  • The very word opal comes from the Sanskrit upala, meaning “precious,” which I guess says it all!

    Zolar’s Magick Of Color Simon 1994

  • The very word opal comes from the Sanskrit upala, meaning “precious,” which I guess says it all!

    Zolar’s Magick Of Color Simon 1994

  • "The opal is oblong," the crystal-gazer continued,

    The Golden Apple Tree 1920

  • The story of the king's opal is the one I know, and though it sounds exactly as though it had been made out of a dream, it is none the less interesting for that, anyone will admit; and this is the story:

    The Golden Apple Tree 1920

  • The town is known as the opal capital of the world because 90% of the world's finest opals are mined there.

    Archive 2009-04-01 Hels 2009

Comments

Log in or sign up to get involved in the conversation. It's quick and easy.

  • Opal. The word itself was like a charm. You could stroke a word like opal. You could taste it. You could swallow it whole, raw and silky, like an oyster, and then Oyster could reel you in.

    --Janette Turner Hospital, 1996, Oyster

    November 11, 2007

  • a town in Wyoming, USA

    February 26, 2008

  • Love this word ;D 'tis my middle name as well

    July 11, 2008

  • Just as well you like it then :-) I did a bit of opal fossicking around Yowah. Fun. I'm easily impressed by shiny things.

    July 11, 2008

  • I'd like to go to Coober Pedy and go down one of the opal mines. Someday.

    July 11, 2008

  • I've been there! It was really cool! Well... actually quite hot. But cool!

    July 11, 2008

  • Stayed about 3 days there in an underground hotel. Certainly a novel experience.

    July 11, 2008