2
unmoved
2
unremitting
1
abounding
1
absolute
1
acceptable(adjective, good, kind, reasonable, fair)
1
adamantine(adjective, strong, hard, tough, sturdy)
1
arbitrary
1
ardent
1
arduous(adjective, tough, rough, difficult, harsh)
1
arrogant
1
assiduous
1
backbreaking(adjective, tough, rough, difficult, heavy)
1
big-hearted(adjective, good, kind, reasonable, fair)
1
bitter(adjective, strong, hard, tough, harsh)
1
bounty
1
brutish
1
bullheaded(adjective, strong, hard, tough, severe)
1
by the book(expression, adjective, idiom, strong, hard)
1
coercive
1
cold-blooded(adjective, tough, harsh, cruel, grim)
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APASmart Define. (2016). unsparing thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/unsparing/thesaurus/synonyms
ChicagoSmart Define. 2016. "unsparing thesaurus" https://smartdefine.org/unsparing/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, unsparing thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/unsparing/thesaurus/synonyms>.
MLASmart Define. "unsparing thesaurus" 24 March 2016. Web. 26 September 2026. <https://smartdefine.org/unsparing/thesaurus/synonyms>