I'm taking Japanese classes at College and I notice my Japanese teacher uses some...questionable diction. For example, when she has us split into pairs, and tells the odd person out to work with another group she says that they can be part of a "threesome". Then she talks about how the vertical line in 事 "penetrates" the others. Now the thing that scares me is that
www.dictionary.com mentions NOTHING about "threesome" being sexually suggestive at all, and the Random House dictionary doesn't mention anything about "penetrate" either.
Now my Japanese teacher speaks English much better than I speak Japanese, so this makes me concerned that I might make a similar faux pas if speak Japanese. Therefore, does anyone know of a Japanese counterpart to
www.urbandictionary.com where this kind of information might be chronicled?