sil·​i·​ca | \ ˈsi-li-kə How to pronounce silica (audio) \

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 Project critics argue that silica is toxic to inhale. Alena Naiden, Anchorage Daily News, 17 May 2022 Currently, the scientists have placed a layer of silica around the magnetic slime. Joshua Hawkins, BGR, 4 Apr. 2022 Chemical analysis showed that the microalgae were mostly made up of silica, but the polymer was rich in sulfur. Jennifer Ouellette, Ars Technica, 26 Apr. 2022 Some cream formulas tend to be heavy on the pores, but the texture on this one is featherlight and smooth, thanks to a combination of silica and soft-focus powders that work pretty much like an IRL beauty filter. Ariana Yaptangco, Glamour, 26 Apr. 2022 The company is actively researching a range of solutions to support the recycling of materials from end-of-life tires and promote the replacement of non-renewable materials such as oil, silica, and virgin carbon black in new tires. Maury Brown, Forbes, 22 Apr. 2022 Cosmetic chemist Ginger King credits silica and clay mineral kaolin for keeping the smudginess at bay. Talia Gutierrez, Allure, 1 Mar. 2022 When rice husks are burned, the ash is rich in high-grade silica. Geoff Colvin, Fortune, 28 Dec. 2021 Borosilicate and silica are the most abundant minerals surrounding the water. Sarah Vitak, Scientific American, 26 Nov. 2021 See More

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.

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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Time Traveler for silica

Time Traveler

The first known use of silica was circa 1801

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Dictionary Entries Near silica



silica aerogel

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Statistics for silica

Last Updated

24 May 2022

Cite this Entry

“Silica.” Dictionary, Merriam-Webster, Accessed 26 May. 2022.

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More Definitions for silica


sil·​i·​ca | \ ˈsil-i-kə How to pronounce silica (audio) \

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

More from Merriam-Webster on silica

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


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