Definition

Noun: 1. An erroneous belief, custom, or practice that is stubbornly adhered to despite clear evidence of its falsehood or impracticality. Specifically, it refers to a person who obstinately clings to such a notion or a habitual error in speech or practice that is persisted in.

Usage

The word "mumpsimus" is a formal and somewhat rare term. It is used to describe a person who is stubbornly wrong or, more commonly, the incorrect belief or practice itself that such a person refuses to change. It carries a strong connotation of willful ignorance and resistance to correction.

Examples

• The professor was a mumpsimus on the topic, refusing to consider any new research that contradicted his 50-year-old thesis.
• His insistence on using the outdated software was pure mumpsimus; everyone else had switched to the more efficient system years ago.
• The ceremony included a mumpsimus—a line mispronounced for generations that no one dared to correct.

Advanced Usage

• To correct a mumpsimus: This phrase means to point out and try to amend a long-held error.
  • The new editor's first task was to correct the stylistic mumpsimus that had plagued the journal for decades.
• The term originates from an anecdote about an illiterate priest who, when corrected for saying "mumpsimus" instead of "sumpsimus" in the Latin Mass, replied he would not change his "old mumpsimus" for the new "sumpsimus."

Variants and Related Words

• Mumpsimuses (plural noun): Multiple instances of such stubborn errors or people who hold them.
  • The committee was full of old mumpsimuses resistant to progress.

Synonyms

• Dogma (an established belief held without proof).
• Superstition (an irrational belief).
• Anachronism (something outdated in the present time).
• Incorrigibility (the quality of being unable to be corrected).

Related Idioms and Phrases

• To cling to a mumpsimus: To stubbornly hold on to an outdated or incorrect idea.
  • Despite all the evidence, he clings to that economic mumpsimus.
• An old mumpsimus: A classic or long-standing error.
  • The policy is just an old mumpsimus that should have been abandoned long ago.

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