ig·​ne·​ous | \ ˈig-nē-əs How to pronounce igneous (audio) \

Definition of igneous

1a : formed by solidification of magma igneous rock
b : relating to, resulting from, or suggestive of the intrusion or extrusion of magma or volcanic activity
2 : of, relating to, or resembling fire : fiery

Examples of igneous in a Sentence

Recent Examples on the Web The singular characteristic of these bays was Great Whin Sill, a band of igneous dolerite — a dusky, crystalline rock — that erupted from the sea in stratified cliffs and headlands. Henry Wismayer, Washington Post, 8 Sep. 2021 But igneous rock like basalt provides a timeline: Scientists can date when the magma turned into hard rock. Matt Simon, Wired, 12 Aug. 2021 Percy may be directed back to this spot to try and grab some igneous rocks in the future, Farley says. Robin George Andrews, Scientific American, 12 Aug. 2021 Perseverance's instruments can zap rocks with lasers to help scientists understand if the rocks on Mars are sedimentary or igneous, which would reveal more about water flow and ancient Martian environments. Ashley Strickland, CNN, 21 July 2021 The Theriac earth of the caves, rich in volcanic dust, black igneous rock, red rock and pumice, is mixed with limestone, and the result is a sturdy plaster that solidifies with humidity and hardens in time. Stav Dimitropoulos, House Beautiful, 22 June 2021 This 867-foot-tall marvel of igneous rock has been sacred to many Northern Plains tribes for millennia; more recently, geologists, rock climbers, and stargazers have flocked to Devils Tower National Monument to revere its otherworldly aesthetics. Outside Online, 17 June 2021 The repository is in 2 billion-year-old igneous Finnish bedrock. James Conca, Forbes, 31 May 2021 One important question scientists want to answer: whether these rocks are sedimentary (like sandstone) or igneous (formed by volcanic activity). Mike Wehner, BGR, 14 May 2021

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

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First Known Use of igneous

1664, in the meaning defined at sense 2

History and Etymology for igneous

Latin igneus, from ignis fire; akin to Sanskrit agni fire

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Time Traveler for igneous

Time Traveler

The first known use of igneous was in 1664

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Dictionary Entries Near igneous

Ignatius of Loyola


igneous fusion

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Statistics for igneous

Last Updated

18 Sep 2021

Cite this Entry

“Igneous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/igneous. Accessed 22 Sep. 2021.

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More Definitions for igneous



English Language Learners Definition of igneous

: formed when hot, liquid rock cools and becomes hard


ig·​ne·​ous | \ ˈig-nē-əs How to pronounce igneous (audio) \

Kids Definition of igneous

: formed by hardening of melted mineral material within the earth igneous rock

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