sub·stra·tum | \ˈsəb-ˌstrā-təm, -ˌstra-;ˌsəb-ˈstrā-, -ˈstra-\
plural substrata\ˈsəb-ˌstrā-tə, -ˌstra-; ˌsəb-ˈstrā-, -ˈstra- \

Definition of substratum 

: an underlying support : foundation: such as

a : substance that is a permanent subject of qualities or phenomena

b : the material of which something is made and from which it derives its special qualities

c : a layer beneath the surface soil specifically : subsoil

d : substrate sense 2

e linguistics : a component of a language (such as a part of its phonology, syntax, or lexicon) that remains from absorption of a pre-existing language in the region where the language is currently spoken

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Other Words from substratum

substratal \ˈsəb-ˌstrā-tᵊl, -ˌstra-; ˌsəb-ˈstrā-, -ˈstra- \ adjective

Examples of substratum in a Sentence

drilled into the bedrock substratum

Recent Examples on the Web

Severance occurs when the tail tip adheres to the substratum and the rest of the planarian pulls away. Chris Ciaccia, Fox News, "Massive 18-inch hammerhead worms are invading France," 23 May 2018 Even here, though, abyssal tuba notes exposed a sonic substratum. Alex Ross, The New Yorker, "The L.A. Philharmonic Celebrates Iceland," 21 Apr. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'substratum.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of substratum

1631, in the meaning defined above

History and Etymology for substratum

Medieval Latin, from Latin, neuter of substratus, past participle of substernere to spread under, from sub- + sternere to spread — more at strew

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The first known use of substratum was in 1631

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English Language Learners Definition of substratum

: a layer of something (such as soil or rock) that is under another layer


sub·stra·tum | \ˈsəb-ˌstrāt-əm, -ˌstrat-, ˈsəb-ˈ \
plural substrata\ \

Medical Definition of substratum 

1 : the material of which something is made and from which it derives its special qualities

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a generally accepted meaning of a word

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