look up any word, like ratchet:
 
1.
A term used to describe someone who is about to get their grind on with a lady.
Corn u is one dirty dog.
by Beth A. November 30, 2007
 
2.
When a person of one gender engages in numerous shady activities with the person of the opposite gender.
Brian: Where did Jonny go?
Kevin: He's at the bookstore with Giraffe woman.
Brian: That dirty dog.
by wonderbrian February 22, 2009
 
3.
An unusual word, in that it is both an adjective AND a noun. You can not only BE a "Dirtydog", you can also act LIKE a "Dirtydog"
To act in a Tiresome fashion, or to moan about everything and everyone that isn't to your taste or agrees with your opinion.

Closely related to the CUNT branch of the adjective family.
"Christ, that Dave is such a Dirtydog at times"
or
"Andy, don't act like a Dirtydog mate, it doesn't fucking suit you"
by The SPS. May 11, 2008
 
4.
A Greyhound bus. See also Filthy Feline.
Nate hopped the Dirty Dog from Minneapolis to Chicago.
by Turd Savant November 16, 2006
 
5.
VERB referring to the acting of rubbing/humping one's crotch and/or bum on someone's belongings. The victim of a Dirty Dog is typically unaware, and it is typically done to a belonging that they would put their face on - often, a pillow. Some victims never know. Others are told by a proud and mocking perpetrator.
Every night, while her sister Fiona was in the shower, Deirdre would Dirty Dog Fiona's pillow. It was her only revenge for her older sister's bullying.
by Garrigan Keeley September 21, 2011
 
6.
The act of sticking a raw hotdog in ones anus and performing anal sex with it as a a dildo then grilling and eating it.
Dude you up for cleaning a dirty dog??
by jwseagles March 28, 2009
 
7.
When having doggy style sex the girl or guy takes a shit
stephanie how did u like the DIRTY DOG
by ajo5 March 26, 2008