"Pā" is a word that comes from the Maori language, which is spoken in New Zealand. It refers to a type of fortified village that was commonly built by the Maori people in the past.
A pā was like a big house, but instead of being just one building, it was a whole bunch of buildings and walls all built together. The walls were made out of dirt and were very high and thick, with lots of little spikes sticking out of them to make it hard for enemies to climb over them.
People would live inside the pā with their families and friends, and they would use it as a safe place to stay when they were being attacked by enemies. They could defend the pā by shooting arrows or throwing rocks at the enemy from the top of the walls.
So basically, a pā was like a big, strong house that had walls all around it to keep the people inside safe from bad guys who might want to hurt them.