Try Our Apps


The Best Internet Slang


[fruhs-tuh m] /ˈfrʌs təm/
noun, plural frustums, frusta
[fruhs-tuh] /ˈfrʌs tə/ (Show IPA).
the part of a conical solid left after cutting off a top portion with a plane parallel to the base.
the part of a solid, as a cone or pyramid, between two usually parallel cutting planes.
Origin of frustum
1650-60; < Latin: piece, bit; probably akin to Old Irish brúid (he) breaks, Old English brȳsan to crush Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
Cite This Source
Examples from the Web for frustum
Historical Examples
  • Wa'al, jest cut off the top, and what's left will be the frustum.

    The Light Keepers James Otis
  • Then follows, in most textbooks, a theorem relating to the volume of a frustum.

    The Teaching of Geometry David Eugene Smith
  • The top of the piston forms the frustum of the cone and the pistons are 110 mm.

    Aviation Engines

    Victor Wilfred Pag
  • A stick of timber is in the shape of the frustum of a square pyramid, the lower base being 22 in.

    The Psychology of Arithmetic Edward L. Thorndike
  • This leads to the corollary concerning the lateral area of the frustum of a regular pyramid.

    The Teaching of Geometry David Eugene Smith
  • If the upper base is equal to the lower base, the frustum becomes a cylinder, and still the proposition remains true.

    The Teaching of Geometry David Eugene Smith
  • The vessel proper was a cylinder; its base, a plane; its top, the frustum of a cone, surmounted by a tower upon a tower.

    A. D. 2000 Alvarado M. Fuller
  • It was built in the form of a frustum of a pyramid, and was fifty-four feet square at the bottom and six feet square at the top.

    The Light Keepers James Otis
  • It is 56 feet high from the rock to the platform or balcony floor, and its shape is the frustum of a cone.

  • The solids divided in given ratios are the sphere, the pyramid, the cone and a frustum thereof.

British Dictionary definitions for frustum


noun (pl) -tums, -ta (-tə)
  1. the part of a solid, such as a cone or pyramid, contained between the base and a plane parallel to the base that intersects the solid
  2. the part of such a solid contained between two parallel planes intersecting the solid
(architect) a single drum of a column or a single stone used to construct a pier
Word Origin
C17: from Latin: piece; probably related to Old English brӯsan to crush, bruise
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for frustum

1650s, from Latin frustum "piece broken off," from PIE *bhrus-to-, from root *bhreu- "to cut, break up."

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source

Word of the Day

Difficulty index for frustum

Few English speakers likely know this word

Word Value for frustum

Scrabble Words With Friends

Nearby words for frustum