Samuel Sandmel defines "parallelomania."
Samuel Sandmel, "Parallelomania," Journal of Biblical Literature 81, no. 1 (March 1962): 1-13
We might for our purposes define parallelomania as that extravagance among scholars which first overdoes the supposed similarity in passages and then proceeds to describe source and derivation as if implying literary connection flowing in an inevitable or predetermined direction.
The key word in my essay is extravagance. I am not denying that literary parallels and literary influence, in the form of source and derivation, exist. I am not seeking to discourage the study of these parallels, but, especially in the case of the Qumran documents, to encourage them. However, I am speaking words of caution about exaggerations about the parallels and about source and derivation. I shall not exhaust what might be said in all the areas which members of this Society might be interested in, but confine myself to the areas of rabbinic literature and the gospels, Philo and Paul, and the Dead Sea Scrolls and the NT.