- Geology. produced under conditions involving intense heat, as rocks of volcanic origin or rocks crystallized from molten magma.
- of, relating to, or characteristic of fire.
Origin of igneous
1655–65; < Latin igneus, equivalent to ign(is) fire + -eus -eous
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for igneous
Traces of it are found in practically all igneous and most sedimentary rocks.Commercial Geography
Jacques W. Redway
The close association both in place and age with igneous rocks.
Igneous rocks are formed by the cooling of molten rock material.
They occur in limestones and shales and are not associated with igneous rocks.
These are characterized by igneous rocks of andesitic nature.The Avifauna of Micronesia, Volume 3
Rollin H. Baker
C17: from Latin igneus fiery, from ignis fire
Word Origin and History for igneous
1660s, from Latin igneus "of fire, fiery," from ignis "fire," from PIE *egni- "fire" (cf. Sanskrit agnih "fire, sacrificial fire," Old Church Slavonic ogni, Lithuanian ugnis "fire").
Online Etymology Dictionary, © 2010 Douglas Harper
- Relating to rocks or minerals formed by the cooling and hardening of magma or molten lava. Basalt and granite are examples of igneous rocks.
- Relating to the processes, such as volcanism, by which such rocks and minerals form.
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