1: Randomly entering nonsensical letter into an online competitive word game, like "Word With Friends" in hopes of the game accepting it.

2: A good excuse for cheating.
*Plays "liripip"*

"Yes! It accepted it!"

"Dude, what the hell was that?!"

"I donno, I was just Letter Mashing....."

*Plays "xylopolist"*

"Hehe 120 points, he can't win now"

"Dude, what the hell was that?!?!"

"I Donno, I was just Letter Mashing"

"Sure dude, sure."
by Raynesta August 12, 2011
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