1) The next level up from 'roflcopter', a transformation of a classic. In disguise. When roflcopter isn't enough, bring in Optimus Prime.
Widely used in London

2) An Idiot/Douche bag
1) Joe: Lol.

Will: Rofl.

Joe: Roflcopter.

Will: Roflmus Prime.

2) Joe: Kat's such an idiot.

Will: Yea, what a Roflmus Prime.
by Hot Rodimus Prime May 4, 2009
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