insurmountable
adj. C1 Advanced US //ˌɪnsɝˈmaʊntəbəɫ// UK //ɪnsəmˈaʊntəbəl// in·sur·mount·able
adj. too large or difficult to deal with. You use this to describe a problem or obstacle that you cannot overcome.
adj. too great to be overcome or surmounted. Often used to describe abstract barriers, challenges, or logistical difficulties.
The team faced insurmountable problems during the first week.
Despite their best efforts, the debt became insurmountable and the small business was forced to close.
The cultural and linguistic barriers proved insurmountable for the new administration, leading to a total breakdown in diplomatic relations between the two neighboring states.
From in- + surmountable.
Usage
Typically used to modify nouns like 'obstacles', 'difficulties', 'problems', or 'odds'.