Definition of "katabatic"

At the field camp, paper-thin tents shudder beneath katabatic blasts of freezing wind, stoves sputter a stingy flame, and a few trudging specks haul shovels through a cold world where extra food and equipment cannot be bought at any price.

2005, Nicholas Johnson, chapter 3, in Big Dead Place

Penguin colonies that number in millions; nights that run into days, and days that run into nights; katabatic winds that scream down the ice sheets at a terrifying 180 miles per hour, and then remain equally terrifyingly still.

2006 February 24, Tishani Doshi, “Meanwhile: The long view from Antarctica”, in The New York Times‎