1660s, from Latin igneus "of fire, fiery," from ignis "fire," from PIE *egni- "fire" (cognates: Sanskrit agnih "fire, sacrificial fire," Old Church Slavonic ogni, Lithuanian ugnis "fire").
例文
1. The most common intrusive in the order of igneous rocks is granite.
火成岩シリーズで最も一般的な侵入体は花崗岩である。
2. Igneous rocks do not contain fossils.
火成岩に化石は含まれていない。
3.The intrusion sequence for igneous rocks is indicated by crosscutting and inclusion relationships.
火成岩の帰属順序は切断と包含関係によって表される。
4.The rocks here are igneous and do not fracture along predictable lines.
ここの石はすべて火成岩で、石の割れ目は極めて不規則である。
5.Thus the intrusive igneous rocks usually have a coarse texture.