Mailboxing 

When a person puts their tongue inside of a uncircumcised penis.

Jenny said she was mailboxing Steve at lunch, she said it tasted like cheese.

Mailboxing by Tuffcuddles June 4, 2019

Mailboxing 

It literally means anything you want it to mean. A placeholder up to your own interruption.

Amber was mailboxing in the public restroom.

You mailboxing bruh.

Mailboxing by BiloxiBacon24 April 20, 2024

Failboxing 

verb

(1)To failbox is to fail or mess up something in a huge way.

(2)To be a failboxer is to be someone who failboxes.
(3) to beatbox horribly

(1)"Yo man i saw you trip down those stairs. You totally failboxed right there"
(2)"shut up you're such a failboxer"
(3)"Dude, that was not beat boxing. That was failboxing."

Failboxing by winteroiceo February 25, 2010