[suhb-strey-tuh m, -strat-uh m, suhb-strey-tuh m, -strat-uh m]

noun, plural sub·stra·ta [suhb-strey-tuh, -strat-uh, -suhb-strey-tuh, -strat-uh] /ˈsʌbˌstreɪ tə, -ˌstræt ə, -sʌbˈstreɪ tə, -ˈstræt ə/, sub·stra·tums.

Compare superstratum.

Origin of substratum

From New Latin, dating back to 1625–35; see origin at sub-, stratum
Related formssub·stra·tive, sub·stra·tal, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for substratum

Historical Examples of substratum

British Dictionary definitions for substratum


noun plural -strata (-ˈstrɑːtə, -ˈstreɪtə)

any layer or stratum lying underneath another
a basis or foundation; groundwork
the nonliving material on which an animal or plant grows or lives
  1. the solid rock underlying soils, gravels, etc; bedrock
  2. the surface to which a fixed organism is attached
sociol any of several subdivisions or grades within a stratum
photog a binding layer by which an emulsion is made to adhere to a glass or film baseSometimes shortened to: sub
philosophy substance considered as that in which attributes and accidents inhere
linguistics the language of an indigenous population when replaced by the language of a conquering or colonizing population, esp as it influences the form of the dominant language or of any mixed languages arising from their contactCompare superstratum (def. 2)
Derived Formssubstrative or substratal, adjective

Word Origin for substratum

C17: from New Latin, from Latin substrātus strewn beneath, from substernere to spread under, from sub- + sternere to spread
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for substratum

1630s, from Modern Latin substratum (plural substrata), neuter singular past participle of Latin substernere "to spread underneath," from sub- (see sub-) + sternere (see stratum).

Online Etymology Dictionary, © 2010 Douglas Harper

substratum in Science


[sŭbstrā′təm, -străt′əm]

Plural substrata substratums

An underlying layer or stratum.
A surface on which an organism grows or is attached; a substrate.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.