Green’s Dictionary of Slang

muhfuh adj.

also muhfug, muh-fuhn

(orig. US) abbr. motherfucking adj.

[US]J. Roe The Same Old Grind 76: ‘You muhfug honky bitch! Doan you be callin’ me no nigguh!’.
[US]S. King Running Man in Bachman Books (1995) 580: Muh-fuhn white honky sumbitch.
[US]F.X. Toole Rope Burns 11: He was framed by the muhfuh white-racist power structure.