: a foliated metamorphic rock corresponding in composition to a feldspathic plutonic rock (such as granite)
Examples of gneiss in a Sentence
Recent Examples on the Web
Fosdick said Connecticut has a lot of variability in its rocks, including granite and gneiss.
—
Jan Ellen Spiegel, Hartford Courant, 23 Feb. 2026
About a dozen of us from an Adventure Canada expedition cruise walked across spongy tundra and up one gnarly gneiss rock formation after another.
—Robert Annis, Travel + Leisure, 16 Feb. 2026
That majestic array of green-gray gneiss sentinels may be the most conceptually elaborate Neolithic monument in Europe.
—Alex Ross, New Yorker, 24 Nov. 2025
The wine comes from vines that grow in the northern part of the Côte Blonde with a soil of gneiss and clay.
—Forbes.com, 14 June 2025
But buried within this ancient gneiss is something even more valuable: zircon.
—Ella Jeffries, Smithsonian Magazine, 16 May 2025
Feldspar and mica, the main minerals in plutonic rocks like granite and metamorphic rocks like gneiss and schist, react with water and oxygen, decaying to clay minerals.
—David Bressan, Forbes, 31 Oct. 2024
The West Kootenay bouldering scene is arguably the fastest growing in Canada, with tons of high-quality gneiss and granite coupled with talented, motivated locals establishing new routes faster than anyone can document.
—Jayme Moye, Outside Online, 4 Oct. 2024
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Jan Ellen Spiegel, Hartford Courant, 23 Feb. 2026
About a dozen of us from an Adventure Canada expedition cruise walked across spongy tundra and up one gnarly gneiss rock formation after another.
—Robert Annis, Travel + Leisure, 16 Feb. 2026
That majestic array of green-gray gneiss sentinels may be the most conceptually elaborate Neolithic monument in Europe.
—Alex Ross, New Yorker, 24 Nov. 2025
The wine comes from vines that grow in the northern part of the Côte Blonde with a soil of gneiss and clay.
—Forbes.com, 14 June 2025
But buried within this ancient gneiss is something even more valuable: zircon.
—Ella Jeffries, Smithsonian Magazine, 16 May 2025
Feldspar and mica, the main minerals in plutonic rocks like granite and metamorphic rocks like gneiss and schist, react with water and oxygen, decaying to clay minerals.
—David Bressan, Forbes, 31 Oct. 2024
The West Kootenay bouldering scene is arguably the fastest growing in Canada, with tons of high-quality gneiss and granite coupled with talented, motivated locals establishing new routes faster than anyone can document.
—Jayme Moye, Outside Online, 4 Oct. 2024
Cite this Entry
“Gneiss.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/gneiss. Accessed 10 Mar. 2026.
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gneiss
noun
: a rock in layers that is similar in composition to granite
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