Green’s Dictionary of Slang

(orig. US) baffling, confusing, amazing.

1971		S.B. Kopp Guru 145: Away from intellectual ‘mind-fucking’ words [HDAS].
2000		T. Prigge Deconstructing Edward Mar. 🌐 ‘Film Rev. of Catch-22’ Unfortunately one of my viewingmates had just a fortnight ago finished the massive, labyrinthine, mindfucking book, and so a lot of it was him reminding me how much of the book was given the cold shoulder.