1. A localized distribution of positive and negative electricity, without a net charge, whose mean positions of positive and negative charges do not coincide.
2. A pair of equal and opposite electric charges, the centers of which do not coincide.
3. Any object or system which is oppositely charged at two points, or poles; such as, a magnet or a polar molecule.
4. A pair of equal and opposite charges an infinitesimal distance apart from each other.

A quantity that is characteristic of a charge distribution, equal to the vector sum over the electric charges of the product of the charge and the position vector of the charge.

The primary process by which an atom produces or absorbs radiation when it changes from one energy level to another one: An electric dipole transition takes place when an oscillating electric field interacts with the electric dipole (a separation of positive and negative charges) movement of an electron inside an atom during which an electric radiation is discharged or absorbed.