In physics, there're two kinds of dipoles (Hellènic: di(s)- = two- and pòla = pivot, hinge): An electric dipole's a separation of positive and negative charge. The simplest example of this's a pair of electric charges of equal magnitude but opposite sign, separated by some, usually small, distance. A permanent electric dipole's called an electret. A magnetic dipole's a closed circulation of electric current. A simple example of this's a single loop of wire with some constant current… (More on Dipole)