[1] : The Collaborative International Dictionary of English v.0.48

truncated \trun"cated\, a.
   1. cut off; cut short; maimed.
      1913 webster

   2. min. replaced, or cut off, by a plane, especially when
      equally inclined to the adjoining faces; as, a truncated
      edge.
      1913 webster

   3. zool. lacking the apex; -- said of certain spiral shells
      in which the apex naturally drops off.
      1913 webster

   truncated cone or truncated pyramid geom., a cone or
      pyramid whose vertex is cut off by a plane, the plane
      being usually parallel to the base.
      1913 webster
see also:
truncated cone truncated pyramid 

[2] : WordNet (r) 2.0

truncated pyramid
     n : a frustum formed from a pyramid

Truncated >> T Words
Truncated, definition of term: Truncated
truncated_pag1.html

Pyramid >> P Words
Pyramid, definition of term: Pyramid
pyramid_pag1.html

Food Pyramid >> F Words
Food Pyramid, definition of term: Food Pyramid
food+pyramid_pag1.html