This is normally associated with sexual intercourse carried out at a rough and vigorous pace (most commonly doggy-style), although it can be associated with any activity where it is performed with gusto. This means that you did whatever it was you were doing with particular enthusiasm and/or speed
Good morning Casper. I had a cracking time knocking the back out of Lady Clementine Smyth last night
or
Gadzooks, I could certainly knock the back out of a few glasses of Moet this evening
or
Gadzooks, I could certainly knock the back out of a few glasses of Moet this evening
by Cockles August 29, 2006
To do a chick doggie style and then all of a sudden pull a "wangthorpe" and sneak your johnson into her bunghole!
by shoesincan November 29, 2012
Said about a sexually appealing woman, with whom you would be very eager to have sex.
To explain the metaphor: you may be a little too vigorous, and push your penis all the way through her, hence, knocking the back out of her... Obviously not physically possible, but a good, although rather crude, metaphor
To explain the metaphor: you may be a little too vigorous, and push your penis all the way through her, hence, knocking the back out of her... Obviously not physically possible, but a good, although rather crude, metaphor
by Dr Mox April 7, 2007