not know (one) from the man in the moon

(redirected from know her from the man in the moon)

not know (one) from the man in the moon

To not know who one is just by looking at them; to have never met one before. (The man on the moon is an image on the visible surface of the moon likened to that of a person's face or body.) Even though Jake had worked at the company for nearly 10 years, the boss still didn't know him from the man in the moon. I don't blame them for not giving me permission right away. They don't know me from the man in the moon.
See also: know, man, moon, not
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.