the.com/polar vortex

means A large, persistent, low-pressure system of frigid air that spins over the poles and, when it wobbles or stretches southward, drags bone-chilling cold into regions far from the Arctic.

from From Latin 'polaris' (of the pole) plus 'vortex,' Latin for a whirling mass of water or air, itself tied to 'vertere,' to turn. Meteorologists have used the term for over a century to describe the stratospheric whirlpool of wind that cages polar cold, but it leapt from textbooks into everyday speech only when disruptions to that wind cage started sending Arctic air spilling into places that weren't used to it — turning a quiet scientific label into a headline phrase almost overnight.