si·​li·​ceous sə-ˈli-shəs How to pronounce siliceous (audio)
variants or less commonly silicious
: of, relating to, or containing silica or a silicate
siliceous limestone

Example Sentences

Recent Examples on the Web Granite is a siliceous stone composed primarily of silicates, such as quartz, feldspar, and mica. Caitlin Sole, Better Homes & Gardens, 4 Aug. 2022 Whereas 95% of Cognac is produced from the Ugni Blanc grape that thrives above limestone soils, grapes for Armagnac include Ugni Blanc, Folle Blanche, Baco and Colombard, which sprout over quartz sand and siliceous clay soils. Tom Mullen, Forbes, 13 Mar. 2022 This giant phosphorescent abstract layered atoll of cascading siliceous marks of what looks like finger paintings made in a cave or a prisoner making counting strokes and notations on a wall. Jerry Saltz, Vulture, 22 Sep. 2021 Siliceous stones include granite, slate, quartzite, soapstone, and sandstone. Seal Team One, The Seattle Times, 15 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'siliceous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


Latin siliceus of flint, from silic-, silex hard stone, flint

First Known Use

circa 1656, in the meaning defined above

Time Traveler
The first known use of siliceous was circa 1656

Dictionary Entries Near siliceous

Cite this Entry

“Siliceous.” Dictionary, Merriam-Webster, Accessed 28 Mar. 2023.

Medical Definition


variants also silicious
: of, relating to, or containing silica or a silicate
a siliceous cement used in dentistry
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