1. the quality or state of having two valences or combining powers, especially in chemistry.
Usage: technical; chemistry
2. in logic and linguistics, the property of having two possible truth values or interpretations.
Usage: formal; logic

Examples

• Oxygen exhibits bivalency in many organic compounds.
• The bivalency of certain elements allows them to form multiple types of bonds.
• In classical logic, bivalency assumes that every proposition is either true or false.
• The principle of bivalency is fundamental to traditional binary systems.
• Sulfur can display bivalency in some chemical reactions.