pyroclastic

adjective

py·​ro·​clas·​tic ˌpī-rō-ˈkla-stik 

: formed by or involving fragmentation as a result of volcanic or igneous action

Examples of pyroclastic in a Sentence

Recent Examples on the Web

Will scientists ever be able to say that a week from now, a certain volcano has an 80% chance of erupting in a particular way — with lava gushing, with a certain explosive force, with pyroclastic flows that will travel down its western flank? —Quanta Magazine, 8 May 2026

Alert 5 means an explosive and life-threatening eruption is underway with deadly volcanic lava and pyroclastic flows and heavy ashfall. —ABC News, 4 May 2026

These avalanches of ash, gas, and rock, known as pyroclastic flows, would wipe out trees, homes, and infrastructure in their path. —Nidhi Sharma, Popular Science, 23 Apr. 2026

These kinds of pyroclastic volcanic eruptions could have conceivably cloaked and preserved ancient organics as well. —Bruce Dorminey, Forbes.com, 2 Sep. 2025

Word History

Etymology

probably from pyro- + clastic

Note: The term was introduced by the English geologist Joseph Beete Jukes (1811-69) in The Student's Manual of Geology, new edition (Edinburgh, 1862), p. 68: "The word 'ash' is not a very good one to include all the mechanical accompaniments of a subaerial or subaqueous eruption, since ash seems to be restricted to a fine powder, the residuum of combustion. A word is wanting to express all such accompaniments, no matter what their size or condition may be, when they are accumulated in such mass so as to form beds of 'rock.' We might call them perhaps 'pyroclastic materials'… ." In the index pyroclastic is glossed as "broken from fire."

First Known Use

1862, in the meaning defined above

Rhymes for pyroclastic

• anaplastic
• bioclastic
• fibroblastic
• hyperplastic
• hypoplastic
• inelastic
• lymphoblastic
• neoplastic
• orgiastic
• periphrastic
• predynastic
• superplastic