la·​pil·​lus | \ lə-ˈpi-ləs How to pronounce lapillus (audio) \
plural lapilli\ lə-​ˈpi-​ˌlī How to pronounce lapillus (audio) , -​(ˌ)lē \

Definition of lapillus

: a small stony or glassy fragment of lava ejected in a volcanic eruption

Examples of lapillus in a Sentence

Recent Examples on the Web This eruption would technically be a vulcanian eruption according to MVO and prevailing winds prevented ash or lapilli from falling on the eastern half of Montserrat. Erik Klemetti, WIRED, "Soufriere Hills continues having a big winter," 8 Feb. 2010

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lapillus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of lapillus

1747, in the meaning defined above

History and Etymology for lapillus

Latin, diminutive of lapis

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The first known use of lapillus was in 1747

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Cite this Entry

“Lapillus.” Dictionary, Merriam-Webster, Accessed 15 Jan. 2021.

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