[ ig-nee-uhs ]
See synonyms for igneous on Thesaurus.com
  1. Geology. produced under conditions involving intense heat, as rocks of volcanic origin or rocks crystallized from molten magma.

  2. of, relating to, or characteristic of fire.

Origin of igneous

First recorded in 1655–65; from Latin igneus “fiery, on fire, burning,” equivalent to igni(s) “fire” + -eus -eous. Ignis is the Latin form of the Proto-Indo-European egni-s, ogni-s, one of the Proto-Indo-European words for “fire,” and it is closely related to Slavic (Polish ) ogień (inflectional stem ogni- ) and to Sanskrit agni- Agni; see fire

Other words from igneous

  • non·ig·ne·ous, adjective

Words Nearby igneous

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use igneous in a sentence

British Dictionary definitions for igneous


/ (ˈɪɡnɪəs) /

  1. (of rocks) derived by solidification of magma or molten lava emplaced on or below the earth's surface: Compare sedimentary, metamorphic (def. 2)

  2. of or relating to fire

Origin of igneous

C17: from Latin igneus fiery, from ignis fire

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for igneous


[ ĭgnē-əs ]

  1. Relating to rocks or minerals formed by the cooling and hardening of magma or molten lava. Basalt and granite are examples of igneous rocks.

  2. Relating to the processes, such as volcanism, by which such rocks and minerals form.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.