unforgivable

/ˌʌnfərˈɡɪvəbəl/
adjective
  1. So bad or wrong that it cannot be forgiven or excused.
    • The company's treatment of its workers was unforgivable.
    • Lying to your best friend is unforgivable.
    • He said something unforgivable during the argument.
Synonyms
What does "unforgivable" mean? | whatsthatwordmean | whatsthatwordmean