1. the quality of being expansive; tendency to expand or grow larger
Usage: often used in physics or technical contexts
2. the quality of being open, communicative, and unreserved in manner

Examples

• The metal's expansivity increases with temperature.
• Thermal expansivity is an important property in engineering design.
• Her natural expansivity made her popular at parties.
• The host's expansivity put all the guests at ease.
• Scientists measured the expansivity of different materials.
• His expansivity in conversation revealed his generous nature.