Polarity

Part of speech: noun (n.)

1. That quality or condition of a body in virtue of which it exhibits opposite, or contrasted, properties or powers, in opposite, or contrasted, parts or directions; or a condition giving rise to a contrast of properties corresponding to a contrast of positions, as, for example, attraction and repulsion in the opposite parts of a magnet, the dissimilar phenomena corresponding to the different sides of a polarized ray of light, etc.

2. A property of the conic sections by virtue of which a given point determines a corresponding right line and a given right line determines a corresponding point. See Polar, n.