in·​sub·​stan·​tial | \ ˌin(t)-səb-ˈstan(t)-shəl How to pronounce insubstantial (audio) \

Definition of insubstantial

: not substantial: such as
a : lacking substance or material nature
b : lacking firmness or solidity : flimsy

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Other Words from insubstantial

insubstantiality \ ˌin(t)-​səb-​ˌstan(t)-​shē-​ˈa-​lə-​tē How to pronounce insubstantiality (audio) \ noun

Synonyms & Antonyms for insubstantial


cobwebby, filmy, flimsy, frothy, gauzy, gossamer, gossamery, sleazy, unsubstantial


sturdy, substantial

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Examples of insubstantial in a Sentence

Their contribution to the fund was insubstantial. as insubstantial as a ghost

Recent Examples on the Web

Artisanal beers are made to be enjoyed on their own, accompanied by nothing more than a bar-top snack or two to complement them — something salty and crunchy and insubstantial. Paul Hodgins,, "Adult Beverages: Beer makes inroads into wine’s world, with mixed results," 6 June 2019 Scholze was bemused by the long theorems with their short proofs, which struck him as valid but insubstantial. Quanta Magazine, "Titans of Mathematics Clash Over Epic Proof of ABC Conjecture," 20 Sep. 2018 The two other justices, Adrienne Grover and Wendy Clark Duffy, also questioned why Multhaup was focusing on the jury's thought process as opposed to a larger claim of insubstantial evidence. Lily Herman, Teen Vogue, "Brock Turner Presents "Outercourse" Argument at Appeals Court," 25 July 2018 In central Illinois, many of those roads are paved with tar and chips or what appears to be a rather thin and insubstantial layer of asphalt. Eric Bangeman, Ars Technica, "All SUV, all of the time: The Range Rover Sport reviewed," 12 July 2018 Visio sees only occasional new features (the differences between Visio 2016 and 2019 are insubstantial), and Microsoft is in the process of rebuilding Project from the ground up, with a greater focus on the cloud and integration with Office 365. Peter Bright, Ars Technica, "Microsoft Office has pretty new icons but they have a fatal flaw," 30 Nov. 2018 Perhaps more of a drawback, although one that often recedes as Krist’s narrative gains momentum, is what the title metaphor implies — an insubstantial and fleeting fiction. Leo Braudy, New York Times, "Los Angeles as the City of Dreams, and Nightmares," 1 June 2018 And how do post offices safely deal with such insubstantial ephemera? Sue Wunder, The Christian Science Monitor, "The payback of follow-through," 23 May 2018 The burden on the university is not insubstantial, but so is the financial benefit received from student tuition. John R. Ellement,, "Mass. high court rules colleges have legal duty to prevent students from committing suicide," 7 May 2018

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

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First Known Use of insubstantial

1607, in the meaning defined above

History and Etymology for insubstantial

probably from French insubstantiel, from Late Latin insubstantialis, from Latin in- + Late Latin substantialis substantial

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Statistics for insubstantial

Last Updated

24 Jun 2019

Look-up Popularity

Time Traveler for insubstantial

The first known use of insubstantial was in 1607

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More Definitions for insubstantial



English Language Learners Definition of insubstantial

: not large or important
: not strong or solid
: not real : not made of a real substance


in·​sub·​stan·​tial | \ ˌin-səb-ˈstan-chəl How to pronounce insubstantial (audio) \

Kids Definition of insubstantial

: not large or important Her contribution was insubstantial.

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More from Merriam-Webster on insubstantial

Thesaurus: All synonyms and antonyms for insubstantial

Spanish Central: Translation of insubstantial

Nglish: Translation of insubstantial for Spanish Speakers

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