witch's were once imagined as old hags with wrinkly skin and icy blood. ha! So the phrase "...colder than a witch's tits..." was used during very cold weather. When someone who still thinks this way came into a warm house or room, often, the phrase would come to mind.
Ol' Harry came into the cabin wrapped up in almost everything he had. The blizzard was just reaching it's peak. He said shiveringly, "DDDDamn! It's ccccolder than a witch's tits out thththere!"
by Cold luvin' Pacific islander August 10, 2006
When it is so cold outside that even the coldest and meanest of evil witches develope a nipple errection that is so hard and pointed that you could cut glass with it or poke someone's eye out with it
by CowboyDave December 17, 2016
by RichKid91 July 11, 2008