Nonvalid and Well-founded
Opposite meaning words
Nonvalid
Nonvalid adjective - Having no basis in reason or fact.
Usage example: a nonvalid theory that most scientists rejected long ago
Well-founded is an antonym for nonvalid.
Well-founded
Well-founded adjective - Based on sound reasoning or information.
Usage example: a well-founded complaint about the business's treatment of its customers
Nonvalid is an antonym for well-founded.
Cite this Source
Well-founded and Nonvalid. (2017). Retrieved 2026, August 13, from https://thesaurus.plus/related/nonvalid/well-founded
Nonvalid & Well-founded. N.p., 2017. Web. 13 Aug. 2026. <https://thesaurus.plus/related/nonvalid/well-founded>.
Well-founded or Nonvalid. 2017. Accessed August 13, 2026. https://thesaurus.plus/related/nonvalid/well-founded.
