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unsubstantial

[ uhn-suh b-stan-shuh l ]
/ ˌʌn səbˈstæn ʃəl /
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adjective

not substantial; having no foundation in fact; fanciful; insubstantial: an unsubstantial argument; unsubstantial hopes.
without material substance: an unsubstantial ghost.
lacking material substance; materially paltry: an unsubstantial dinner of bread and cheese.
lacking strength or solidity; flimsy: an unsubstantial wall of cardboard.

RELATED WORDS

unreal, fragile, frail, thin, imaginary, unbelievable, vaporous, visionary, aerial, diaphanous, ethereal, filigree, inane, shadowy

Nearby words

  1. unstuck,
  2. unstudied,
  3. unsub,
  4. unsubscribe,
  5. unsubsidized,
  6. unsubstantiated,
  7. unsubtle,
  8. unsuccess,
  9. unsuccessful,
  10. unsuitable

Origin of unsubstantial

late Middle English word dating back to 1425–75; see origin at un-1, substantial
Related formsun·sub·stan·ti·al·i·ty, nounun·sub·stan·tial·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unsubstantial

British Dictionary definitions for unsubstantial

unsubstantial

/ (ˌʌnsəbˈstænʃəl) /

adjective

lacking weight, strength, or firmness
(esp of an argument) of doubtful validity
of no material existence or substance; unreal
Derived Formsunsubstantiality, noununsubstantially, adverb
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 unsubstantial

unsubstantial

adj.

mid-15c., from un- (1) "not" + substantial.

Online Etymology Dictionary, © 2010 Douglas Harper