Slicker than snot on a doorknob

Meaning

Used to describe a surface that is extremely slippery or treacherous. It is meant to be slightly gross to emphasize just how dangerous the footing is.

Crude, colorful

Used in a sentence

• Be careful on the porch because the ice is slicker than snot on a doorknob.
• That new floor polish is slicker than snot on a doorknob.
• Those old tires made the road feel slicker than snot on a doorknob.