Enter a clue or pattern or both:
The Clue
Diehard of a sort (9 letter answer)
The Answer
MUMPSIMUS
Tags
Notes
The answer MUMPSIMUS is so rare that it appears less than once every 2500 puzzles.
Definition
MUMPSIMUS as a noun:
1. a traditional notion that is obstinately held although it is unreasonable; "he still holds to the old mumpsimus that a woman's place is in the kitchen"