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Synonyms

well-founded

American  
[wel-foun-did] / ˈwɛlˈfaʊn dɪd /

adjective

  1. having a foundation in fact; based on good reasons, information, etc..

    well-founded suspicions.
well-founded British  

adjective

  1. having good grounds

    well-founded rumours
"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

Etymology

Origin of well-founded

Middle English word dating back to 1325–75

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.