Sumpsimus

Word of the Day for Monday, July 2, 2012

sumpsimus \SUHMP-suh-muhs\, noun:

1. Adherence to or persistence in using a strictly correct term, holding to a precise practice, etc., as a rejection of an erroneous but more common form (opposed to mumpsimus).
2. A person who is obstinate or zealous about such strict correctness (opposed to mumpsimus).

And now let all defenders of present institutions, however bad they may be — let all violent supporters of their old mumpsimus against any new sumpsimus whatever, listen to a conversation among some undergraduates.
-- Frederic William Farrar , Julian Home

She is a master of sumpsimus, more anal in language usage than Doc in his rigid professionalism. She insists on saying It is I, or He gave the book to John and me.
-- Ann Burrus, Astride the Pineapple Couch

Like its counterpart mumpsimus, sumpsimus comes from to a story about an illiterate priest. In this case, sumpsimus refers to the opposite practice as mumpsimus. 

Thanks to: www.dictionary.com