unnamable

/ʌnˈneɪməbəl/
adjective
  1. Impossible or very difficult to name or describe because it is too strange, powerful, or vague.
    • There was an unnamable quality to the music that made it unforgettable.
    • She felt an unnamable fear as she entered the dark forest.
    • The painting evoked an unnamable sadness in everyone who saw it.
Antonyms
What does "unnamable" mean? | whatsthatwordmean | whatsthatwordmean