Meaning "Don't Make That Dirty"...This is said after you realize you have set someone up perfectly for a "that's what she said" joke or some other dirty comment.
Michael: So how was your rowing practice out on the river this morning?
Veronica: It was long and hard...I am so worn out and sore...
(moments later)
Veronica: Oh my god Michael dmtd!!!
Veronica: It was long and hard...I am so worn out and sore...
(moments later)
Veronica: Oh my god Michael dmtd!!!
by VinnyT:) August 19, 2009