If there's ice outside in Pennsylvania-especially central/pa dutch areas-it's "slippy" out there. I caught a German speaking cab customer use the word while speaking to her husband. I started to laugh, explaing why I was doing so. She said that she never used that word but her husband agreed with me, saying that she did. They only moved to Penn State/State College 2 years before and our colloquialsms were growing on them.