plutonism noun. ['plu:t(ǝ)nɪz(ǝ)m] In sense 1 usu. Plutonism. M19.
[from PLUTONIC + -ISM.]
Geology.
1. Hist. The theory that the rocks of the earth's crust were formed primarily by solidification from magma, rather than by precipitation from the sea. Cf. NEPTUNISM. M19.

2. Geological activity associated with the formation of plutons. M20.

■ Plutonist noun (Hist.) an advocate of Plutonism L18.

[TahlilGaran] English Dictionary ▲