What is the name of the 3D triangle with 2 triangular faces and a rectangular base?

You are probably referring to the triangular prism?

More in -depth info on:
http://en.wikipedia.org/wiki/Prism_(geometry)

Pyramid but that has 3 or 4 faces. I am confused since only 2 faces can't give you 3D. Prism works if you left out the 2 rectangular faces not on the base.