The definition of igneous is something produced by volcanic action or intense fire.(adjective)
Rocks that have formed from solidified lava from a volcano are an example of rocks that would be described as igneous.
See igneous in Webster's New World College Dictionary
Origin: L igneus < ignis, a fire < IE base *egnis > Sans agníḥ, fire, Lith ugnìs
See igneous in American Heritage Dictionary 4
Origin: From Latin igneus
Origin: , from ignis, fire.
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