5
cat-hearted(adjective, person, unwarmhearted)
5
disciplined(adjective, severe)
5
fiendish(adjective, person, unwarmhearted)
5
fundament
5
gloomy
5
half-spirited(adjective, person, unwarmhearted)
5
hard-boiled(adjective, hard, tough, severe, rough)
5
hard-line(adjective, hard, tough, severe, rough)
5
hateful(adjective, person, unwarmhearted)
5
headstrong(adjective, hard, tough, rough, harsh)
5
immovable(adjective, determined, resolute, rigid, uncompromising)
5
inclement(adjective, hard, tough, severe, rough)
5
indecent(adjective, person, unwarmhearted)
5
inhumane(adjective, person, unwarmhearted)
5
intractable(adjective, appearance, terrible, persistent, obstinate)
5
iron(adjective, persistent, obstinate, insistent, dogged)
5
keen(adjective, severe)
5
mummified(adjective, person, unwarmhearted)
5
nates
5
pitiless(adjective, mean, hard, severe, sharp)
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APASmart Define. (2016). stern thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/stern/thesaurus/synonyms
ChicagoSmart Define. 2016. "stern thesaurus" https://smartdefine.org/stern/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, stern thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/stern/thesaurus/synonyms>.
MLASmart Define. "stern thesaurus" 24 March 2016. Web. 22 September 2026. <https://smartdefine.org/stern/thesaurus/synonyms>