Doubtful and Unsolved

Doubtful

Doubtful adjective - Not feeling sure about the truth, wisdom, or trustworthiness of someone or something.

Unsolved and doubtful are semantically related In some cases you can use "Unsolved" instead an adjective "Doubtful".

Unsolved

Unsolved adjective - Not solved.

Doubtful and unsolved are semantically related in uncertain topic. You can use "Doubtful" instead an adjective "Unsolved".
Cite this Source
Unsolved and Doubtful. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/doubtful/unsolved
Doubtful & Unsolved. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/doubtful/unsolved>.
Unsolved or Doubtful. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/doubtful/unsolved.
Google Ngram Viewer shows how "doubtful" and "unsolved" have occurred on timeline