pyroclastic

American  

[pahy-ruh-klas-tik] / ˌpaɪ rəˈklæs tɪk /

adjective

Geology.

1. composed chiefly of fragments of volcanic origin, as agglomerate, tuff, and certain other rocks; volcaniclastic.

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pyroclastic British  

/ ˌpaɪrəʊˈklæstɪk /

adjective

1. (of rocks) formed from the solid fragments ejected during a volcanic eruption

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pyroclastic Scientific  

/ pī′rō-klăs′tĭk /

1. Composed chiefly of rock fragments of explosive origin, especially those associated with explosive volcanic eruptions. Volcanic ash, obsidian, and pumice are examples of pyroclastic materials.

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Etymology

Origin of pyroclastic

First recorded in 1885–90; pyro- + clastic

Example Sentences

See Examples For:

pyroclastic

As the title suggests, “Out of Time” is less about the living city than the dying one, with a sliver of hope carved out of the ash, rubble and pyroclastic surge.

From Los Angeles Times ● Jul. 22, 2026

The rise and collapse of the eruption column presaged a series of pyroclastic surges, the fourth of which killed everyone in its path in Pompeii.

From The Wall Street Journal ● Jan. 2, 2026

The temperature of the pyroclastic flows that buried Herculaneum and Pompeii was several hundreds of degrees Celsius, hot enough to easily burn and destroy soft tissue.

From Salon ● Mar. 4, 2025

A fast-moving current of hot gas and volcanic matter, also called a pyroclastic flow, followed, burying the area.

From BBC ● Feb. 27, 2025

“Back in 1980,” explained Janine Krippner, a volcanologist who has done research on the pyroclastic flows on Mount St. Helens, “you had these seismographs printed on paper.”

From "Mountain of Fire" by Rebecca E. F. Barone