silica

noun

sil·​i·​ca ˈsi-li-kə How to pronounce silica (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
From their sample, around one-third of extreme debris disks are silica-rich disks. — Robert Lea, Space.com, 6 Oct. 2026 Ripple Hollow, another roadless area, contains silica deposits. — Christiana Freitag, Chicago Tribune, 4 Oct. 2026 Starship’s heat shield is composed of approximately 18,000 hexagonal tiles made of silica ceramic. — Sven Bilén, The Conversation, 29 Sep. 2026 The formula includes microporous silica to mattify the skin and absorb excess sebum and bakuchiol to regulate sebum over time. — Reece Andavolgyi, InStyle, 24 Sep. 2026 See All Example Sentences for silica

Word History

Etymology

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

First Known Use

circa 1801, in the meaning defined above

Time Traveler
The first known use of silica was circa 1801

Phrases Containing silica

Rhymes for silica

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Browse Nearby Words

silic-
silica
silica aerogel
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Cite this Entry

“Silica.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/silica. Accessed 14 Oct. 2026.

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Kids Definition

silica

noun
sil·​i·​ca ˈsil-i-kə How to pronounce silica (audio)
: a compound that consists of the dioxide of silicon and occurs in various forms (as in quartz, opal, and sand)

Medical Definition

silica

noun
sil·​i·​ca ˈsil-i-kə How to pronounce silica (audio)
: 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

Britannica.com: Encyclopedia article about silica

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