3
inspissate(verb, set, swell, strengthen, dry)
3
lacking humanity(verb, feel, emotions, bad action)
3
look hostile(verb, feel, emotions, bad action)
3
look savage(verb, feel, emotions, bad action)
3
naturalize(verb, impulse, toughen)
3
numb(verb, thicken, stabilize, toughen, season)
3
settle(verb, close, set, develop, secure)
3
turn to stone(expression, idiom, clarify, solidify)
3
vitiate(verb, feel, emotions, bad action)
3
warp(verb, feel, emotions, bad action)
2
add to(verb, expression, support, increase, develop)
2
become one(verb, expression, meet, join, link)
2
beef up(verb, expression, support, increase, boost)
2
blight(dry, burn, brand, scorch, solder)
2
blunt(verb, thicken, stabilize, toughen, season)
2
break in(verb, expression, study, develop, improve)
2
calloused(verb, adjective, jellied, gel, calcify)
2
callus(noun, verb, calcify, thicken, stabilize)
2
chasten
2
close(verb, set, settle, firm, solid)
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APASmart Define. (2016). harden thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/harden/thesaurus/synonyms
ChicagoSmart Define. 2016. "harden thesaurus" https://smartdefine.org/harden/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, harden thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/harden/thesaurus/synonyms>.
MLASmart Define. "harden thesaurus" 24 March 2016. Web. 26 September 2026. <https://smartdefine.org/harden/thesaurus/synonyms>