Incidental and Key
Opposite meaning words
Incidental
Incidental adjective - Lacking importance.
Usage example: we still have to work out a few incidental details, but the proposal is largely complete
Key is an antonym for incidental.
Key
Cite this Source
Key and Incidental. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/incidental/key
Incidental & Key. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/incidental/key>.
Key or Incidental. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/incidental/key.
Google Ngram Viewer shows how "incidental" and "key" have occurred on timeline