ADJECTIVE (3)

1. of or relating to manic depressive illness;

2. of, pertaining to, or occurring in both polar regions;
- Example: "the bipolar distribution of certain species"

3. having two poles;

The Collaborative International Dictionary of English v.0.48:

Bipolar \Bi*po"lar\, a. [Pref. bi- + polar. Cf. Dipolar.]
   Doubly polar; having two poles; as, a bipolar cell or
   corpuscle.
   [1913 Webster]

The Free On-line Dictionary of Computing (17 December 2009):

bipolar

   1.  See bipolar transistor.

   2.  In digital transmission, an electrical
   line signalling method where the mark value alternates between
   positive and negative polarities.

   See also AMI.

   (1995-03-02)