Because its base is a square.
It is just called a square pyramid, but its not square. Its only square on the bottom, so they call it a square pyramid, or you can simply just call it a pyramid because a pyramid is a pyramid.
It is simply called a square based pyramid
The scientific name for a square base pyramid is a "square pyramid." It is a type of pyramid where the base is a square and the triangular sides meet at a common apex point.
A square based pyramid is a 3-d object. It does not have a 2-d name!
It is a square based pyramid. And the word is which, not witch!
A square based pyramid is the best name. It is a pentahedron, but that could also refer to a pyramid on any quadrilateral base and so the name is far less informative.
You cannot have a 2d pyramid - whether or not it is square based. The 2d cross section will depend on the plane of the cross section.
A square pyramid's base is a square. You can tell by the name (for exp. a triangular pyramid's base is a triangle.) Good luck with whatever you need it for :)
4 triangles and 1 square
The PYRAMIDS at Giza in Egypt. Hence the name 'pyramid'.
Square pyramid
Oh, dude, another name for a square-based pyramid is a "pyramid with a square base." Like, it's literally in the name. It's not rocket science, just a pyramid chillin' on a square. So, yeah, square-based pyramid, that's the vibe.