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5.
laughing sinisterly to myself
im a steal your car... lstm
by Kelmasonly April 08, 2009
 
1.
Laughing-Silently-To-Myself. The REAL alternitive to LOL, because really how often are you laughing out loud when you type LOL. Exactly. Not too often. And when you are laughing out loud, use LOL, otherwise: LSTM.
Sue: hey brad, guess what?
Brad: what?
Sue: I have Herpes :(
Brad: LSTM
Sue: That wasn't a joke!!
Brad: oh . . . sorry . . LOL!
by !jkmc? July 02, 2009
 
2.
laughing silently to myself
like when ur on aim but u really aint lauging out loud u use this cuz its funny but that not funny
steven :pete's snoring

ada :lstm
by Steven To September 09, 2007
 
3.
'Laughing silently to myself.'

Because sometimes "LOL" is a lie.
"Your mom."
"LSTMS." -dies a little inside-
by Danime-33 November 22, 2007
 
4.
laugh silently to my self
did u see joey today? lstm

i didnt want to be rude so i had to lstm.

u failed ur test? lstm
by co-inventor of ^^®™ January 04, 2012