Definition of silica
: the dioxide of silicon SiO2 occurring in crystalline, amorphous, and impure forms (as in quartz, opal, and sand respectively)
Recent Examples of silica from the Web
Karen went to a new doctor, who told her that there’s increasing consensus that lupus can be brought on by environmental triggers, including exposure to contaminants and chemicals, like cigarette smoke, silica, and mercury.
Available for dry, thinning and oily hair, the beauty-boosting supplements are packed with nourishing ingredients like biotin, omega 3 and silica.
Whether ultimately kitschy, classical, utilitarian or visionary, all hot glasswork starts with melting batches of silica sand, soda ash and limestone in a 2,400 degree Fahrenheit furnace for blowing, casting into molds and other processes.
The terraces, a large, bright white and pink set of cascading rocks, were once considered the largest deposit of silica sinter, a type of quartz.
The company has taken dust samples from the air to test for silica particles, which can be harmful to people's health.
During the early months of the Trump administration, a former lobbyist for an industry group that has opposed the beryllium, silica and record-keeping rules served on the transition team at the Department of Labor, which oversees OSHA.
The grains, of course, were eaten long ago and the plant stalks have long been rotten, but one tiny part of rice remains even thousands of years later: phytoliths, or hard, microscopic pieces of silica made by plant cells for self-defense.
Factories that produce plate glass—by pouring thin layers of molten silica onto baths of molten tin—can be hotter.
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
First Known Use: circa 1801See Words from the same year
SILICA Defined for English Language Learners
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
Seen and Heard
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