Bipyramidal

1 definition found

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

  Bipyramidal \Bi`py*ram"i*dal\, a. [Pref. bi- + pyramidal.]
     Consisting of two pyramids placed base to base; having a
     pyramid at each of the extremities of a prism, as in quartz
     crystals.
     [1913 Webster]