10
inexcusably(adverb, unforgivably)
7
unforgivably
3
dreadfully
3
excessively
3
intolerably
3
unduly
3
unjustifiably(adverb, inexcusably)
2
awfully
2
indefensibly(adverb, inexcusably)
2
irremissibly
2
reprehensibly(adverb, inexcusably)
2
terribly
1
agonizingly
1
bitterly
1
blatantly
1
cruelly
1
deadly
1
deathly
1
distressingly
1
excruciatingly
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APASmart Define. (2015). unpardonably thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/unpardonably/thesaurus/synonyms
ChicagoSmart Define. 2015. "unpardonably thesaurus" https://smartdefine.org/unpardonably/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, unpardonably thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/unpardonably/thesaurus/synonyms>.
MLASmart Define. "unpardonably thesaurus" 14 April 2015. Web. 21 September 2026. <https://smartdefine.org/unpardonably/thesaurus/synonyms>