[ suhmp-suh-muh s ]
/ ˈsʌmp sə məs /

noun, plural sump·si·mus·es for 2.

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).
a person who is obstinate or zealous about such strict correctness (opposed to mumpsimus).

Origin of sumpsimus

First recorded in 1540–50; see origin at mumpsimus Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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