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understratum

American  
[uhn-der-strey-tuhm, -strat-uhm] / ˈʌn dərˌstreɪ təm, -ˌstræt əm /

noun

plural

understrata, understratums

  1. a substratum.

Etymology

Origin of understratum

First recorded in 1725–35; under- + stratum

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.