Having a large and squarish head that resembles a mailbox. A lot of the times people with mailbox heads eat ass. occasionally they will have spiked or raised hair resembling the flag on a mailbox.
by DatManT January 15, 2017

by Solid Mantis July 19, 2018

by Solid Mantis July 19, 2018

by Bruce god4eva Campbell July 25, 2008

One's ass when referred to as a recepticle
by Ham Cannon November 6, 2003

Steven Hawkings: (In robot voice) Im going to Indiana Mailbox your mother.
Annr Frank: Don’t do me like that bruv, please no.
Annr Frank: Don’t do me like that bruv, please no.
by DaddyDuerk February 13, 2019

by voiceofstl March 18, 2021
