2. A virulent Chinese curse, as per WMD and NMD. This is usually used of a thing or person in the third person. The meaning is somewhat akin to "that jerk" or "this useless piece of crap". Literally it means "of its/his/her mother".
2. Chinese President Hu Jintao: "WTF is Bush talking about?"
Taiwanese President Chen Shui-Bian: "Dude, I don't know. TMD."
Chinese President Hu Jintao: "Damn straight. TMD. Nice spliff, BTW."
Taiwanese President Chen Shui-bian: "Thx."
It's the catch phrase for university programs at the University of Michigan, but it is generally used sarcastically by the student body as a punch line to statements regarding UM-stereotypes.
Reference themichdiff.com for more examples.
Our bathroom stalls have more intellectual thought than the entire MSU undergrad curriculum. TMD