polar

adj

1.
having a pair of equal and opposite charges
Derived from:
polarity pole
2.
characterized by opposite extremes; completely opposed
Derived from:
polarity pole
3.
located at or near or coming from the earth's poles
Pertainym:
pole
Derived from:
pole
4.
of or existing at or near a geographical pole or within the Arctic or Antarctic Circles
Antonym:
equatorial
Derived from:
pole
6.
being of crucial importance