When ancient Egyptians first came to Middle East the three great Pyramids along with many other massive ruins were already there, they named them after pyres upon which originally they burned their dead.
The three great pyramids of Egypt were called Ganen ar Ge'nez in the distant ancestor of the proto-semitic language of the region which meant quite literally Shining Peaks.
The name itself came from the constant energy discharge in the form of a pillar of light radiating skywards from the capstones.
The term pyramid was not present at that time in any reconstructed language of that age.