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

Examples of siliceous in a Sentence

Recent Examples on the Web Warm hydrogen glows pinkish-purple in the image, while cosmic dust, composed of tiny grains of siliceous (rocky) and carbonaceous (sooty) material, appears reddish-brown. Phil Plait, Scientific American, 14 June 2024 According to data from the U.S. Geological Survey, the region’s land consists of shallow marine sediments, soft siliceous sedimentary mudstone and shale — many of which can shift with changes in weight load and pressure. Ryan Fonseca, Los Angeles Times, 12 July 2023 This non-slip stone mat, which was featured in a TikTok video that's racked up more than 173,000 views, is made of siliceous sedimentary rock, which can hold up to 150 percent of its weight in moisture and dries in seconds, leaving you with a clean, mold-free surface every time. Stephanie Montes, Travel + Leisure, 20 June 2023 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 examples are programmatically compiled from various online sources to illustrate current usage of the word 'siliceous.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 22 Jul. 2024.

Medical Definition


variants also silicious
: of, relating to, or containing silica or a silicate
a siliceous cement used in dentistry
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!