INSUBSTANTIAL Synonyms: 70 Similar and Opposite Words

insubstantial

adjective

ˌin(t)-səb-ˈstan(t)-shəl

as in unsubstantial

being of a material lacking in sturdiness or substance an insubstantial carton that could not possibly stand up during long-distance shipping

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Antonyms & Near Antonyms

as in spiritual

not composed of matter energy is insubstantial

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Antonyms & Near Antonyms

Example Sentences

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Recent Examples of insubstantial And since the lesser and insubstantial always has to give place to the greater and substantial, self-indulgent lust has no choice but to make way for our reflection of pure and perfect Love. —

Tony Lobl, Christian Science Monitor, 28 Oct. 2025 Republican lawmakers and state attorneys general have challenged the basis of those recommendations, arguing that the evidence used to support them is insubstantial. —

Selena Simmons-Duffin, NPR, 1 Aug. 2025 Vague green claims won’t cut it anymore, as evidenced by a 2020 study from the European Commission, which found over half of environmental claims were insubstantial, misleading or unfounded. —

Alexandra Harrell, Sourcing Journal, 2 July 2025 These insubstantial claims did not improve much after the European powers departed. —

Michael Barnes, Austin American Statesman, 2 July 2025 See All Example Sentences for insubstantial

Recent Examples of Synonyms for insubstantial

Adjective

This can alter the amount and types of ACE-inhibiting peptides created during fermentation2—and possibly account for kombucha's unsubstantial effect on blood pressure.

— MD Published, Verywell Health, 27 Dec. 2025
Then again … This really does sum up Reeves’s unsubstantial performance as Jonathan Harker, whose new client is definitely up to no good.

— Tim Grierson, Vulture, 18 Oct. 2025