knocking on the back door 

n. when a man attempts anal sex without requesting verbal permission. Often involves either precursory acts such as foreplay (rimming, anal fingering) or preceding acts (spreading of ass checks, tapping head of penis on anus, pushing the tip of the penis onto the orifice without full insertion) to signal one's attempt at anal intercourse.

After doing it doggystyle with Jackie, I started knocking on the back door. She didn't object so I totally stuck it in her butt until she screamed.

Richard Johnson kept knocking on the backdoor last night in bed, but I told him to stop since I barely know him.

knocking on the back door by calisp August 1, 2013

throwing stones at the back door 

wanting to take a shit but there are no facilities around so you gotta hold it.

the cosby kids are throwing stones at the back door.

throwing stones at the back door by Merf July 7, 2003

knock the back door in and put the extension up 

Polite euphemism for anal sex, just crying out to be written into an updated Carry On film based around DIY enthusiasts.

Jack Douglas : "I'll be finished as soon as I've knocked her back door in and put me extension up"
Sid James : "Hwar har har!"

knock the back door in and put the extension up by TC Raymond August 15, 2005

push the snake out the back door 

Taking a shiznazzle. Dropping the Cosby's off at the pool. Firing off a missle. Pinching a loaf. Breaking one off. Pooping. Shitting. A thick fart.

Oh snap, I went to toot and accidentally pushed the snake out the back door.

push the snake out the back door by bt March 5, 2003

kick the back door in 

to park your pink vehicle in her brown garage (with force)

I flipped her over and kicked the back door in!!

kick the back door in by G August 4, 2003

The back door Ballard County slaw dog

While wearing a bomber green condom you Lube a girl's butt up with Hellman's mayonnaise inline her butt cheeks with slaw then violently anally penetrated her

Oh yeah I was back behind the grocery store the other day giving this girl The back door Ballard County slaw dog.

The back door Ballard County slaw dog by Cairo Jerry July 12, 2019

Use the back door 

This is when the woman is on the rag painting the front porch and you bang her in the ass.

"She was painting the front porch, so I had to use the back door."

Use the back door by Leon Sema November 22, 2005