An expression used to vent frustration/pain/almost any other feeling expressed by the word fuck, typically as an alternative to mother fucker with the added emphasis of the mother being unholy (except for it is a mother of fuck, and not a fucker of mothers).
Unholy mother of fuck! What is that?!
*stubs toes on coffee table*
UNHOLY MOTHER OF FUCK! FUCKING COFFEE TABLES!
*stubs toes on coffee table*
UNHOLY MOTHER OF FUCK! FUCKING COFFEE TABLES!
by fuckyeahnico December 10, 2010