The other definition here claiming that yin yang refers to anus is correct, and older people in certain regions of the US know this very well. This site is for "slang" usages, not the formal dictionary definition which would refer to the Chinese symbol. When a person says something like, "Wow, this store has widgets up the yin yang", it does not mean plethora. Rather, it's a substitution for the word ass. And in a sexual context, yin yang does indeed refer to the anus. "Taking it up the yin yang" is probably the most used phrase, although it's now somewhat antiquated, and it means taking it up the anus, or male/female part which is common to men and women, which is how the word was derived since the Chinese symbol represents the male/female balance.
by meknow October 08, 2009
The anus. Yin in Chinese philosophy refers to feminine energy, while yang refers to masculine energy. The word has been incorporated into American slang to mean the male/female part. In effect, while males and females have different sexual organs, the anus is common to both sexes, thus the use of yin(female), and yang(male), to denote the anus in sexual contexts. Infrequently used.
by tortfeasor January 12, 2006
Ross couldn't decide whether he wanted to hit on Rachel or stay in the closet and masturbate with Joey. What a yin yang!
by Neil Gendreau October 15, 2007
When a guy and a girl 69 eachother and then the girl shoots her cottage cheese discharge into the guys mouth while he poops in her mouth. (the person on top has to put their mouth over the hole and suck it out)
by Justin :) February 27, 2008
by tomix4000 September 23, 2010
Okay... Don't listen to anyone else because most of them are dumbasses. The spiral (Yin-Yang) is most commonly Good and Evil (White and Black), but it can be among other things as long at it's opposing the other.
Dan: Yin Yang Is spelled Y-I-N-G Y-A-N-G. Cory: No, dumbass, read a book, it's spelled Y-I-N Y-A-N-G.
by Tristan` July 13, 2008