What does "unipolar" mean?

Unipolar: (Anat.) Having but one pole or process; -- applied to those ganglionic nerve cells which have but one radiating process; -- opposed to multipolar. Unipolar induction (Elec.), induction, as in a conducting circuit, by only one pole of a magnet. -- Unipolar stimulation (Physiol.), the simulation sometimes produced when one electrode of an induction apparatus is applied to a nerve; -- called also unipolar induction action. Du Bois-Reymond.