unascertainable

/ˌʌnæsərˈteɪnəbəl/
adjective
  1. Impossible to find out or discover with certainty.
    • The author's true identity is unascertainable from the surviving manuscripts.
    • The exact cause of the ancient fire remains unascertainable due to lack of evidence.
    • In many cold cases, the truth is unascertainable after so many years.
What does "unascertainable" mean? | whatsthatwordmean | whatsthatwordmean