noun
definition
A cone or pyramid whose tip has been truncated by a plane parallel to its base.
definition
A portion of a sphere, or in general any solid, delimited by two parallel planes.
Examples of frustum in a Sentence
Hence the area of an ellipse whose axes are 2a and 2b is Trab; and the volume of an ellipsoid whose axes are 2a, 2b and 2c is t rabc. The area of a strip of an ellipse between two lines parallel to an axis, or the volume of the portion (frustum) of an ellipsoid between two planes parallel to a principal section, may be found in the same way.
The volume of a frustum of a cone, for instance, can be expressed in terms of certain magnitudes by a certain formula; but not only will there be some error in the measurement of these magnitudes, but there is not any material figure which is an exact cone.
This pulley has fixed to one side, and concentric with it, a short frustum of a hollow cone.
This frustum is made always to turn along with the shaft by being fitted on a square portion of it, or by means of a rib and groove, or otherwise, but is capable of a slight longitudinal motion, so as to be pressed into, or withdrawn from, the hollow cone by means of a lever.
At a small distance from the pulley the shaft carries a short frustum of a solid cone accurately turned to fit the hollow cone.