Green’s Dictionary of Slang

(US) a euph. synon. for motherfucker n.

1977		Maledicta 1 (Summer) 11: There is also a whole lesser spectrum of obviously burlesque and mocking synonyms for the same thing, such as granny-jazzer, mammy-jammer, momma-hopper, and poppa-lopper. These are used to raise a laugh, not to start a fight.
1989		H. Rawson Dict. of Invective (1991) 258: The degree of outrage was evidenced by the number of euphemisms that were devised for the expression, e.g., granny-jazzer, mammy-jammer, mommy-hopper, mother-grabber, mother-jumper, and mother-lover, among others.