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
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.
The material, a mix of liquid polymers and silica (tiny sandlike particles), is called shear thickening fluid.
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 1801
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
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