sil·​i·​ca | \ˈsi-li-kə \

Definition of silica 

: the dioxide of silicon SiO2 occurring in crystalline, amorphous, and impure forms (as in quartz, opal, and sand respectively)

Examples of silica in a Sentence

Recent Examples on the Web

And the chemical signatures in those glass pieces matched silica from the region around Samarra. Kiona N. Smith, Ars Technica, "Medieval artisans built a glass-walled palace in the desert," 31 Aug. 2018 Dust samples taken from nine apartments in May by consultants Olmsted Environmental Services turned up dangerously high levels of lead and crystalline silica. Garance Burke, The Seattle Times, "Tenants allege Kushner firm pushed them out of their homes," 17 July 2018 This jar is made of silica glass, which can handle a 180 degree Fahrenheit temperature change. 9. Kevin Dupzyk, Popular Mechanics, "Watch What Happens When We Take Apart a Blender," 10 June 2015 The robot started with a layer of silica, the main component of sand, and used the ion beam to shape the walls and cut out the windows and door. Denise Chow /, NBC News, "Why scientists created the world's smallest house," 30 May 2018 For a truly one-of-a-kind experience, book an in-water treatment where you will be massaged while floating in the silica-rich waters of the lagoon itself. Lyndsey Matthews, Town & Country, "See Inside the Retreat at Blue Lagoon Iceland, the Blue Lagoon's First Five-Star Hotel," 11 June 2018 The water is comprised of silica, algae and minerals. Liz Dufour, USA TODAY, "WOW Air stopover: Photos of 82 hours in Iceland," 25 May 2018 At the beach, silica sand mixes with fragments of coral, shell and other material of biological origin. Discover Magazine, "20 Things You Didn't Know About ... Sand," 18 May 2018 For example, silica, which makes up around 60 percent of windblown desert dust, is known to cause chronic lung inflammation, lung cancer and autoimmune diseases. Smithsonian, "How Climate Changed-Fueled “Mega Droughts” Could Harm Human Health," 12 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'silica.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of silica

circa 1801, in the meaning defined above

History and Etymology for silica

New Latin, from Latin silic-, silex hard stone, flint

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Statistics for silica

Last Updated

20 Nov 2018

Look-up Popularity

Time Traveler for silica

The first known use of silica was circa 1801

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English Language Learners Definition of silica

: a chemical that contains silicon, that is found in sand and quartz, and that is used to make glass


sil·​i·​ca | \ˈsil-i-kə \

Medical Definition of silica 

: the dioxide of silicon SiO2 that is used as an ingredient of simethicone and that occurs naturally in crystalline, amorphous, and impure forms (as in quartz, opal, and sand respectively)

called also silicon dioxide

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More from Merriam-Webster on silica

Spanish Central: Translation of silica

Nglish: Translation of silica for Spanish Speakers Encyclopedia article about silica

Comments on silica

What made you want to look up silica? Please tell us where you read or heard it (including the quote, if possible).


to enclose within walls

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