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Supposedly vs. Supposably


[fuh-ley-shuh s] /fəˈleɪ ʃəs/
containing a fallacy; logically unsound:
fallacious arguments.
deceptive; misleading:
fallacious testimony.
disappointing; delusive:
a fallacious peace.
Origin of fallacious
1500-10; < Latin fallāciōsus deceitful, deceptive. See fallacy, -ous
Related forms
fallaciously, adverb
fallaciousness, noun
nonfallacious, adjective
nonfallaciously, adverb
nonfallaciousness, noun
unfallacious, adjective
unfallaciously, adverb Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the Web for fallacious
Contemporary Examples
Historical Examples
  • Got in light and fallacious ways, the money dwindles; only when gathered by labour does it really increase.

  • Still, through this fallacious medium, a real enlargement of ideas is attained.

    The Republic Plato
  • The fallacious assumption implied in the query, quid Christianis cum regibus?

    The Cradle of Mankind W.A. Wigram
  • Only what must be avoided are fallacious inferences, my dear Lena—especially at this hour.

    Victory Joseph Conrad
  • The very greatest care is necessary to determine what facts are true and what are fallacious.

    Expository Writing Mervin James Curl
  • There has never been a religion too gross, too fallacious, to fail of followers.

    The Tyranny of the Dark Hamlin Garland
  • What became of his fallacious hope of waiting when events were driving on at this rate?

    That Fortune Charles Dudley Warner
  • No compromise for him, no evasions, no fallacious, unsecured promises to pay.

    Dream Days Kenneth Grahame
  • Subsequently another company was formed in New York, being influenced by a fallacious view of the silicious sand.

British Dictionary definitions for fallacious


containing or involving a fallacy; illogical; erroneous
tending to mislead
delusive or disappointing: a fallacious hope
Derived Forms
fallaciously, adverb
fallaciousness, noun
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
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Word Origin and History for fallacious

c.1500, from fallacy (Latin fallacia) + -ous. Related: Fallaciously; fallaciousness.

Online Etymology Dictionary, © 2010 Douglas Harper
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