pozzolana
/ˌpɑtsəˈlɑnə/
noun
- A volcanic ash from Pozzuoli, Italy, used in ancient Roman concrete that hardens under water.
- The Romans imported pozzolana from the Bay of Naples to build the Pantheon.
- Pozzolana gives Roman concrete its remarkable ability to set in seawater.
- Archaeologists study pozzolana to understand ancient construction techniques.