insurmountable

/IH0 N S ER0 M AW1 N T AH0 B AH0 L/
adjective
  1. 1

    Incapable of being passed over, surmounted, or overcome; insuperable

    โ€œGetting everybody to agree proved to be an insurmountable difficulty.โ€

Antonyms

Source: https://en.wiktionary.org/wiki/insurmountable