When a man has sex with someone from behind implying anal sex, although it can also mean regular sex Doggy Style.
I bust in on them and there he was hanging out the back of her.

Dave: Crikey mate look at that piece over there
Alan: Golly Gosh I'd love to hang out the back of that!
by Jack T August 30, 2005
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to have casual sex with someone not close. not complimentary term for making love.

"didn't you hang out the back of some bird last night"
by martin butters November 21, 2007
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"oi dave what did you do this weekend"?
"well Al, i was on a knobout round my mates gaff and i was terrorising this bird, and there i was hanging out the back of it when my mate burst in" !!
" i said you know i looked good hanging out the back of it though init"!!
by im the daddy October 29, 2006
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"I'd love to hang out the back of that"

Davy: "My burd is on holiday in ibiza, do you think she will get up to anything?"

Rab: "Your kidding someone will be hanging out the back of her"
by Rodehard August 21, 2008
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a girl with an ass so fat that it protrudes below her shorts or skirt and sometimes pants.

an ass so big you can set your drink on it tabletop
that girl's ass was hanging out the back so far she got carpet burn on her ass cheeks.

it was sweet going to the club with her, because she could hold my drink on her ass the was hanging out the back
by MurryG May 1, 2005
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Apart from the original Richard Keys usage of the phrase, to hang out the back of something can be used as an expression of approval of something well done.
(after eating a good meal cooked by a friend) "that pasta was great, you really hang out the back of it"
by Rolfparis April 8, 2012
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