not know (one) from a hole in the wall(redirected from don't know you from a hole in the wall)
not know (one) from a hole in the wall
To not know who one is just by looking at them; to have never met one before. Even though Jake had worked at the company for nearly 10 years, the boss still didn't know him from a hole in the wall. I don't blame them for not giving me permission right away. They don't know me from a hole in the wall.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.