1. an alloy of gold or silver with a base metal (such as copper), especially when the base metal is present in a large proportion
Usage: metallurgy
2. debased gold or silver
Usage: historical

Examples

• The ancient coins were made of billon rather than pure silver.
• Medieval currencies often used billon to reduce the cost of minting.
• The jeweler explained that billon contains more copper than precious metal.
• Archaeologists found billon artifacts at the excavation site.
• The museum’s collection includes several billon coins from the Roman era.