Fortuitous and Sure

Fortuitous

Fortuitous adjective - Happening by chance.
Usage example: firmly believes that the creation of the universe was something other than just the fortuitous coming together of particles of matter

Sure is an antonym for fortuitous.

Sure

Sure adjective - Having or showing a mind free from doubt.

Fortuitous is an antonym for sure.

Nearby Word: surely
Cite this Source
Sure and Fortuitous. (2016). Retrieved 2026, August 14, from https://thesaurus.plus/related/fortuitous/sure
Fortuitous & Sure. N.p., 2016. Web. 14 Aug. 2026. <https://thesaurus.plus/related/fortuitous/sure>.
Sure or Fortuitous. 2016. Accessed August 14, 2026. https://thesaurus.plus/related/fortuitous/sure.
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