1. a siliceous or aluminous material that reacts with calcium hydroxide in the presence of water to form compounds with cementing properties
Usage: technical; construction

Examples

• Fly ash is a common pozzolan used in concrete production.
• The ancient Romans used volcanic ash as a natural pozzolan in their cement.
• Adding pozzolan to concrete can improve its durability and strength.
• Silica fume is a highly reactive pozzolan that reduces concrete permeability.
• The engineer specified a pozzolan additive to enhance the concrete’s performance.
• Natural pozzolans include volcanic ash, pumice, and diatomaceous earth.