lmtd

This is another one of those internet/text message abbreviations.
In brief: lmtd = laugh(ed/ing) myself to death
As an extreme degree of hysterical laughter, this a step up from rofl or lmao.

"Dude, did you see the Billy Mays auto-tuned vid?"

"Yeah, lmtd!!"

by JD "Lennon" November 30, 2009