[ fruhs-tuh m ]
/ ˈfrʌs təm /

noun, plural frus·tums, frus·ta [fruhs-tuh] /ˈfrʌs tə/. Geometry.

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 Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for frusta

British Dictionary definitions for frusta

/ (ˈfrʌstəm) /

noun plural -tums or -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 for frustum

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