: a foliated metamorphic rock corresponding in composition to a feldspathic plutonic rock (such as granite)
gneissic adjective
gneissoid adjective
gneissose adjective

Examples of gneiss in a Sentence

Recent Examples on the Web Be sure to visit this Blue Ridge Parkway town and its namesake geological formation — an ancient gneiss outcrop whose rocky bulk causes the wind to blow vertically, making objects appear to float skyward. Anne Olivia Bauso, Travel + Leisure, 11 Apr. 2024 Back then, her great-great-great-uncle, the Viscount of Bom Retiro, expropriated private lands on behalf of the Brazilian state to reforest Rio’s peaks of granite and gneiss, which had been denuded by the growing coffee industry. Michael Snyder Pedro Kok, New York Times, 22 Mar. 2024 One billion years ago, following millennia of uplift and erosion, the gneiss breached the surface with its psychedelic ripples and baroque bands—the gray and pink of quartz, feldspar, and granite; the dark green and black of hornblende and biotite mica. Hugh Raffles, The New York Review of Books, 9 Oct. 2020 Outcrop of banded gneiss in the Canadian shield. Gemma Tarlach, Discover Magazine, 15 May 2013 But its two-billion-year-old vertical black gneiss walls have been almost inaccessible for millennia, even to the Ute, the first inhabitants of this region. Stephanie Pearson, Outside Online, 2 Nov. 2022 His sculpture in the exhibition is a stylized face of granitic gneiss, its hair indicated by a tuft from a musk ox. Peter Saenger, WSJ, 28 Oct. 2022 The home is built of native gneiss granite, some quarried from the Willimantic River. Melanie Savage, Hartford Courant, 27 Oct. 2022 Black Canyon is a park of extremes, both fertile springtime folly and menacing gash of gneiss and schist. Emily Pennington, Outside Online, 28 Aug. 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'gneiss.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


German Gneis, alteration of Middle High German gneiste spark, from Old High German gneisto; akin to Old English fȳrgnāst spark

First Known Use

1757, in the meaning defined above

Time Traveler
The first known use of gneiss was in 1757

Dictionary Entries Near gneiss

Cite this Entry

“Gneiss.” Dictionary, Merriam-Webster, Accessed 15 Apr. 2024.

Kids Definition


: a rock in layers that is similar in composition to granite

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