permittivity
/ˌpɜrmɪˈtɪvɪti/
noun
- A measure of how easily an electric field can pass through a material, or how well a material stores electrical energy.
- The permittivity of air is much lower than that of water.
- Engineers measure the permittivity of different plastics to design better capacitors.
- High permittivity materials are used in smartphone antennas to improve signal strength.