Definition of pluton in English:

pluton

Pronunciation /ˈplo͞otän/ /ˈplutɑn/

noun

Geology
  • A body of intrusive igneous rock.

    • ‘The igneous complex is composed of four steep-walled plutons separated by country rock septa and surrounded by a zone of small stocks and veins.’

Origin

1930s back-formation from plutonic.