coined by Robert *Graves no less

Graves? I don't think so. B&M OED gives 1856 for the first citation. It's a translation of Seneca's word apocolocyntosis from his tribute to the god Claudius upon his death, APOCOLOCYNTOSIS DIVI CLAVDII. And *he got it from the Greek apokolokyntosis, transformation into a pumpkin. Ain't *that some pumpkins!

http://www.thelatinlibrary.com/sen.apoc.html