means A solid geometric shape with a polygonal base whose sides rise to meet at a single apex, most famously the colossal stone tombs built by ancient Egyptian pharaohs.

from From the Greek 'pyramis' (plural 'pyramides'), the word the Greeks used for those Egyptian monuments. The Greeks' own term may be borrowed from the Egyptian word for the structures, though its deeper roots are debated; one charming folk story links it to 'pyra' (fire) or even to a kind of wheat cake shaped like the monuments — but these are likely later wordplay rather than the true source. From Greek the word passed into Latin as 'pyramis' and on into the European languages.