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Electric dipole radiation is electromagnetic radiation (EMR) generated by an oscillating electric dipole. An electric dipole is the electric field formed by a pair of locations with opposite charge, and such an oscillation can be electrons cycling back and forth at some frequency between locations such that the two locations exchange polarity. The shifting electric field creates a magnetic field, with field lines encircling the dipole axis, that oscillates at the same frequency, and together the two oscillating fields form electro-magnetic waves with the frequency of the oscillation. The waves propagate in essentially all directions, but maximally in the directions perpendicular to the axis of the dipole, the strength falling to none in the two directions parallel to the axis. This type of radiation is generated by any wire carrying an alternating current, US power producing (very weak) subradio waves of 60 Hz (5000 km wavelength). Antennas used for radio transmission (particularly, dipole antennas) purposely do this at radio frequencies, and the inverse process is the mechanism of antennas used for reception.
Some types of EMR scattering consist of the scatterer-particle essentially acting as a receiving antenna which sets its charge-configuration into a dipole oscillation, causing it to transmit using the energy of the absorbed EMR and can be usefully modeled as such. As described above, transmission is in all directions but mostly perpendicular to the dipole. Evidence that radiation is from an electric dipole as well as orientation of the dipole axis can be gleaned from resulting polarization.
The term electric dipole radiation is often used specifically for a particular mathematical model of such radiation, a simplification of the mathematics of electromagnetism that effectively models the mechanism described above.