from The American Heritage® Dictionary of the English Language, 5th Edition.

  • adjective Lacking material substance; insubstantial.
  • adjective Lacking firmness or strength; flimsy.
  • adjective Lacking basis in fact.

from The Century Dictionary.

  • Not substantial; not solid: as, unsubstantial air. Not real; not having substance; imaginary; illusive: as, unsubstantial forms. Not having good substance; not strong or stout: as, an unsubstantial building; unsubstantial cloth.
  • Not giving substance or strength; weak; not strengthening or invigorating.

from the GNU version of the Collaborative International Dictionary of English.

  • adjective Lacking in matter or substance; visionary; chimerical.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective archaic Alternative form of insubstantial.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adjective lacking material form or substance; unreal


Sorry, no etymologies found.


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  • "Something like a London fog" it has been called, "only a dust fog," – an animated fog in which everything unsubstantial is fair prey.

    Canadian Cities of Romance 1922

  • Funny that a video about information literacy includes such an unsubstantial claim.

    What is Information Literacy? (Otis College) « Information Literacy Videos « Videos « Literacy News 2009

  • His flesh as unsubstantial as cobwebs, veins and arteries, tendons and muscles all clear beneath the ethereal shine of translucent skin.

    Earl of Durkness Alix Rickloff 2011

  • But I still think it remains a fair question: Would the not-unsubstantial investment in an MSR mission designed to ferry a cache of tiny surface scratchings to earthside labs be all that more efficient/cost-effective than sending along a team of trained geologists to manage the collection with a robust on-site laboratory available for immediate assessment of specimen value?

    Mars Program Gets no Special Treament - NASA Watch 2009

  • His flesh as unsubstantial as cobwebs, veins and arteries, tendons and muscles all clear beneath the ethereal shine of translucent skin.

    Earl of Durkness Alix Rickloff 2011

  • There's nothing like emotional substance, even in an ostensibly unsubstantial thriller.

    'Contraband': Almost Illegally Entertaining Joe Morgenstern 2012

  • Even before the protests, female political power and representation in Mubarak's Egypt was unsubstantial and token at best.

    Ehsan Zaffar: The Revolution Isn't Over for the Women of Tahrir Square Ehsan Zaffar 2011

  • Front, Churchill in his latest push had expressed unshaken confidence in the allied conduct of the war, and Roosevelt according to a recent speech was supremely optimistic as to the final outcome of the conflict, all very vague and unsubstantial, but, heartening, never the less.

    Work Camp 10760 L 2010

  • To say that Colbert's testimony was surprisingly unsubstantial, if funny, would be unfair, because it would imply we expected celebrity testimony before congress to be anything other than unsubstantial.

    Stephen Colbert testimony: a mockery, but of whom? Alexandra Petri 2010

  • You never report facts until unsubstantial claims contrary to the truth have been proven false, ( 'ie death panels, the public option is a government take over of health care), and then you want to do your so called fact check, it's more like, after the fact check.

    CNN Truth Squad: Will health-care reform start right away? 2009


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