un ‧ just ‧ i ‧ fi ‧ a ‧ ble /ʌnˈdʒʌstəfaɪəb ə l, ʌnˈdʒʌstɪfaɪəb ə l/ BrE AmE adjective
[ Word Family: adjective : ↑ justifiable ≠ ↑ unjustifiable , ↑ justified ≠ ↑ unjustified ; verb : ↑ justify ; noun : ↑ justification ; adverb : ↑ justifiably ≠ ↑ unjustifiably ]
completely wrong and unacceptable:
Poisoning the earth’s atmosphere is ecologically and morally unjustifiable.
—unjustifiably adverb