frus·​tule ˈfrəs-(ˌ)chül How to pronounce frustule (audio)
: the 2-valved siliceous shell of a diatom

Word History


French, from Latin frustulum, diminutive of frustum

First Known Use

1848, in the meaning defined above

Time Traveler
The first known use of frustule was in 1848

Dictionary Entries Near frustule

Cite this Entry

“Frustule.” Dictionary, Merriam-Webster, Accessed 1 Apr. 2023.

More from Merriam-Webster on frustule

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