unanswerable

/ˌʌnˈænsərəbəl/
adjective
  1. Impossible to answer or refute; having no known solution or reply.
    • The question of why we exist is often considered unanswerable.
    • Her argument was so logical that it seemed unanswerable.
    • The detective faced an unanswerable puzzle with no clues.
What does "unanswerable" mean? | whatsthatwordmean | whatsthatwordmean