silica

noun sil·i·ca \ ˈsi-li-kə \

|Updated on: 19 Jun 2018

Definition of silica

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

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Recent Examples of silica from the Web

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
As New Atlas explains, engineers used a focused ion beam to cut a flat sheet of the silica membrane.

— liz stinson, Curbed, "This is truly the world’s tiniest tiny house," 25 May 2018
The rocks are obsidian, a silica-heavy glass that formed near the end of the eruption cycle of nearby Mount Konocti, last active about 11,000 years ago.

— esther mobley, San Francisco Chronicle, "The rise of the Red Hills of Lake County," 1 June 2018
To assemble the walls, the robot used the beam to score the silica without cutting all the way through, Rauch said, and then the structure was folded into place like origami.

— denise chow /, NBC News, "Why scientists created the world's smallest house," 30 May 2018
The silica membrane bungalow was constructed on a 300 by 300 micrometer plot of wire via a nanorobotics system that makes use of an ion gun, gas injection system, and vacuum chamber.

— liz stinson, Curbed, "This is truly the world’s tiniest tiny house," 25 May 2018
The water is blue due to the way the silica reflects sunlight.

— liz dufour, USA TODAY, "WOW Air stopover: Photos of 82 hours in Iceland," 25 May 2018
Because they are made of silica-rich continental rock, which makes a stickier lava, these volcanoes tend to form towering cones that erupt with a blast.

— author: scott wilson, sarah kaplan, Anchorage Daily News, "As Kilauea erupts, volcanologists swarm: ‘I expect great science from this event’," 24 May 2018
That silica content is the key to understanding why Kilauea behaves differently from volcanoes seen on land.

— sarah gibbens, National Geographic, "No, Hawaii's Volcano Won't Trigger a Mega-Tsunami," 17 May 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.

Origin and Etymology of silica

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

NEW! Time Traveler

First Known Use: circa 1801

in the meaning defined above

See Words from the same year

SILICA Defined for English Language Learners

silica

noun

Definition of silica for English Language Learners

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

Medical Dictionary

silica

noun 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