unknowable

From un- +‎ knowable.

unknowable (comparative more unknowable, superlative most unknowable)

1. Not knowable; not able to be known.

   Synonyms: unintelligible; see also Thesaurus:incomprehensible

   Antonyms: knowable; see also Thesaurus:comprehensible

   • 2004, George Carlin, “NINETY-NINE THINGS YOU NEED TO KNOW”, in When Will Jesus Bring the Pork Chops?‎, New York: Hyperion Books, →ISBN, →OCLC, →OL, page 39:

     Number fourteen: Some of the things you need to know are things that are unknowable.

• unknowability

unknowable (plural unknowables)

1. Something that cannot be known.