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unfounded

American  
[uhn-foun-did] / ʌnˈfaʊn dɪd /

adjective

  1. without foundation; not based on fact, realistic considerations, or the like.

    unfounded suspicions.
    Synonyms:
    unjustified, false, idle, groundless, unsubstantiated

  2. not established; not founded.

    the prophet of a religion as yet unfounded.
unfounded British  
/ ʌnˈfaʊndɪd /

adjective

  1. (of ideas, allegations, etc) baseless; groundless

  2. not yet founded or established

"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

Other Word Forms

  • unfoundedly adverb
  • unfoundedness noun

Etymology

Origin of unfounded

First recorded in 1640–50; un- 1 + found 1 + -ed 2

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.