4
terrible(adjective, revengeful)
4
unkind(adjective, mean, hard, severe, harsh)
3
demoniac(adjective, pitiless)
3
determined(adjective, harsh, cruel, fierce, persistent)
3
difficult(adjective, hostile, demanding, exacting)
3
dismal
3
fiendish(adjective, pitiless)
3
fierce(adjective, mean, hard, tough, severe)
3
hostile(adjective, person, feelings, response, demanding)
3
insensitive(adjective, hard, tough, harsh, cruel)
3
intractable(adjective, hard, severe, rough, harsh)
3
malevolent(adjective, mean, harsh, cruel, vicious)
3
rancorous(adjective, mean, harsh, cruel, vicious)
3
shameful
3
stony-hearted(adjective, revenge)
3
strict(adjective, hard, rough, harsh, cruel)
3
stringent(adjective, harsh, cruel, determined, fierce)
3
unmoved(adjective, pitiless, intolerant)
3
vicious(adjective, mean, hard, severe, rough)
2
antagonistic(adjective, reactive, reciprocal, vindictive, tit-for-tat)
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APASmart Define. (2016). unforgiving thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/unforgiving/thesaurus/synonyms
ChicagoSmart Define. 2016. "unforgiving thesaurus" https://smartdefine.org/unforgiving/thesaurus/synonyms (accessed September 28, 2026).
HarvardSmart Define 2016, unforgiving thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/unforgiving/thesaurus/synonyms>.
MLASmart Define. "unforgiving thesaurus" 24 March 2016. Web. 28 September 2026. <https://smartdefine.org/unforgiving/thesaurus/synonyms>