frus·​tum | \ ˈfrə-stəm How to pronounce frustum (audio) \
plural frustums or frusta\ ˈfrə-​stə How to pronounce frustum (audio) \

Definition of frustum

: the basal part of a solid cone or pyramid formed by cutting off the top by a plane parallel to the base also : the part of a solid intersected between two usually parallel planes

Examples of frustum in a Sentence

Recent Examples on the Web The EmDrive test device used by White and his colleagues was a copper frustum—a cone with its top lopped off—that was just under a foot long. Daniel Oberhaus, Wired, 8 May 2020

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

First Known Use of frustum

1658, in the meaning defined above

History and Etymology for frustum

New Latin, from Latin, piece, bit — more at bruise entry 2

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Time Traveler for frustum

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The first known use of frustum was in 1658

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Cite this Entry

“Frustum.” Dictionary, Merriam-Webster, Accessed 12 Jun. 2021.

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