Fantastic and Unconceivable

Fantastic

Fantastic adjective - Too extraordinary or improbable to believe.
Usage example: concocted some fantastic story to try to explain why they had returned home so late

Unconceivable and fantastic are semantically related. In some cases you can use "Unconceivable" instead an adjective "Fantastic".

Unconceivable

Unconceivable adjective - Too extraordinary or improbable to believe.
Usage example: it's unconceivable that a once-promising actor could end up this way

Fantastic and unconceivable are semantically related. Sometimes you can use "Fantastic" instead an adjective "Unconceivable".
Cite this Source
Unconceivable and Fantastic. (2016). Retrieved 2026, August 02, from https://thesaurus.plus/related/fantastic/unconceivable
Fantastic & Unconceivable. N.p., 2016. Web. 02 Aug. 2026. <https://thesaurus.plus/related/fantastic/unconceivable>.
Unconceivable or Fantastic. 2016. Accessed August 02, 2026. https://thesaurus.plus/related/fantastic/unconceivable.
Google Ngram Viewer shows how "fantastic" and "unconceivable" have occurred on timeline