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Quote:
mumpsimus noun ( pl. -muses) a traditional custom or notion adhered to although shown to be unreasonable. • a person who obstinately adheres to such a custom or notion. ORIGIN mid 16th cent.: erroneously for Latin sumpsimus in quod in ore sumpsimus ‘which we have taken into the mouth’ (Eucharist), in a story of an illiterate priest who, when corrected, replied “I will not change my old mumpsimus for your new sumpsimus.”