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Rupert's drop

noun
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Ru·​pert's drop | \ ˈrüpərts- \

Definition of Rupert's drop

: a congealed blob of glass formed by dropping melted glass into water and setting up such residual stresses that the globule explodes violently when the surface is scratched or a piece broken off

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History and Etymology for Rupert's drop

after Prince Rupert of Germany †1682 who first brought it to England to his uncle Charles I of England

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Cite this Entry

“Rupert's drop.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Rupert%27s%20drop. Accessed 18 Sep. 2020.

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