Question

what is dielectric constant in simple words

Answer 1

It is also known as Relative permittivity.
The dielectric constant of the medium is the ratio of the absolute electrical permittivity of vaccum to the absolute electric permittivity of the medium.
In other words, dielectric constant is the ratio of the force of attraction or repulsion between the two similar point charges to the ratio of the force of attraction or repulsion between point charges separated by some distance.