Definitions

1. noun

the process or movement of molten rock from the interior of the Earth to the surface, resulting in the formation of volcanoes and the eruption of lava, ash, and gases.

“The geologist studied the effects of vulcanism on the surrounding landscape.”

2. noun

a type of rock or mineral deposit formed as a result of vulcanism, such as volcanic ash or lava rock.

“The ancient civilization built their city on a site rich in vulcanism, using the volcanic ash to create durable buildings.”