(dī’ pōl) 1. A pair of equal charges or poles of opposite signs that ideally are infinitesimally close together. 2. In resistivity and IP surveying, a pair of nearby current electrodes that approximates a dipole field from a distance, or a voltage-detecting electrode pair. Where the electrode separation is large, it is sometimes called a bipole. 3. In electromagnetic surveying, an electric- or magnetic-field transmitting or receiving antenna which is small enough to be represented mathematically as a dipole. The near fields (electric and magnetic) from a magnetic and electric dipole (respectively) vary as the inverse cube of the distance.