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mysteriousness

American  
[mi-steer-ee-uhs-nis] / mɪˈstɪər i əs nɪs /

noun

  1. the quality of being full of mystery or suggesting a mystery.

  2. the quality of being beyond understanding or difficult to figure out.

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.