Synonyms of unjustifiably

2 Syllables
wrongly
3 Syllables
unduly, unjustly, wrongfully, groundlessly
4 Syllables
illegally, illicitly, erroneously, unlawfully
5 Syllables
unpardonably, indecorously, inexcusably, prejudicially, indefensibly
7 Syllables
disproportionately, illegitimately