An abbr. of motherfucking in an effort to be more politically correct, "PG", or safe for work.
M'er'f'in yessssssss!!!!!

That m'er'f'in bitch was a fucking whore ass dipshit at the party last night.

Mom! I'm on my m'er'f'in way back home. Chill!

Awwww yeahhhhh, m'er'f'in cheeze burgerzzz...
by manofwar July 4, 2014
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