polar

Being of crucial importance.

“the polar events of this study”

“a polar principal”

Characterized by opposite extremes; completely opposed.

“extreme and indefensible polar positions”

Extremely cold.

“polar weather”

Having a pair of equal and opposite charges.

Of or existing at or near a geographical pole or within the Arctic or Antarctic Circles.

“polar regions”

Located at or near or coming from the earth's poles.

“polar diameter”

“polar zone”