silica

noun

sil·​i·​ca ˈsi-li-kə 

: 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

Many brands are moving away from talc products and instead formulating with alternatives that can provide the same blurring, anti-caking action like cornstarch, rice starch, mica and silica without the cancer risk. —Helen Carefoot, Flow Space, 11 Dec. 2025

The unnamed patient reportedly performed activities such as cutting, grinding and polishing, which can generate crystalline silica dust. —Bonny Chu, FOXNews.com, 11 Dec. 2025

In 2009, to halt the spread of silicosis, Turkey banned the use of sandblasting materials containing silica. —Angela Velasquez, Sourcing Journal, 9 Dec. 2025

Whitehaven Beach spans seven kilometers of pure silica sand, while Hill Inlet's swirling sand forms a mesmerizing natural masterpiece. —Suzy Mercien-Ferol, Travel + Leisure, 3 Dec. 2025

Word History

Etymology

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

First Known Use

circa 1801, in the meaning defined above

Phrases Containing silica

• silica gel
• vitreous silica

Rhymes for silica

• basilica

Kids Definition

silica

noun

sil·​i·​ca ˈsil-i-kə 

: 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 

: 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