unconceivable

/ˌʌnkənˈsivəbəl/
adjective
  1. Impossible to imagine or believe; not able to be conceived.
    • The scale of the damage after the earthquake was unconceivable.
    • The idea of traveling to another galaxy was unconceivable a century ago.
    • It is unconceivable that she would lie to her best friend.
Antonyms
What does "unconceivable" mean? | whatsthatwordmean | whatsthatwordmean