IPA: /pərˈmɪtɪvɪti/
KK: /pərˈmɪtɪvɪti/
A measure of how well a material can store electrical energy when an electric field is applied to it.
The permittivity of the material affects how capacitors function in electronic circuits.
Permittivity is formed from "permittere" (meaning to allow) and the suffix "-ivity" (indicating a quality or state). The word refers to the quality or state of allowing electric field lines to pass through a material, thus describing how easily a material can permit electric field lines.
Think of 'allowing' ('permittere') something to happen, and remember that 'permittivity' describes how easily a material allows electric fields to pass through it.