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

Pyroclastic flow can be very dangerous to the surrounding area, but there has been no indication of an imminent threat.

From BBC • Jun. 2, 2025

Pyroclastic flows — avalanches of rock, ash and volcanic gas — burst from the mountain’s actively growing lava dome inside the crater.

From Seattle Times • Aug. 8, 2021

Pyroclastic flows and lahars hitting the ocean can also displace water on an alarming scale.

From Scientific American • Mar. 24, 2019

Pyroclastic flows, as the New York Times pointed out, are far more dangerous than the lava flows of Hawaii’s Kilauea volcano because they are, essentially, avalanches of ultra-hot gas and rock.

From Slate • Jun. 4, 2018

Pyroclastic texture is usually recognized by the chaotic mix of crystals, angular glass shards, and rock fragments.

From Textbooks • Jan. 1, 2017