127 entries under set topic. ×

9
steel(verb, support, close, increase)
8
acclimatize(verb, close, continue, firm)
8
acclimate(verb, close, keep, overcome)
8
clot(verb, form, close, develop)
7
anneal(verb, support, close, increase)
7
buttress(verb, support, close, increase)
7
compact(verb, close, develop, secure)
7
dry(verb, take, close, settle)
7
firm(verb, close, settle, solid)
7
fossilize(verb, close, settle, firm)
6
concrete(verb, close, firm, solid)
6
nerve(noun, verb, close, settle)
5
callous(verb, close, settle, firm)
5
caseharden(verb, close, continue, firm)
5
crystallize(verb, form, close, develop)
5
vitrify(verb, close, settle, firm)
4
calcify(verb, close, settle, firm)
4
gel(verb, form, develop, combine)
4
gird(verb, support, close, settle)
3
amalgamate(verb, close, meet, develop)
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APASmart Define. (2016). harden thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/harden/thesaurus/synonyms
ChicagoSmart Define. 2016. "harden thesaurus" https://smartdefine.org/harden/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, harden thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/harden/thesaurus/synonyms>.
MLASmart Define. "harden thesaurus" 24 March 2016. Web. 25 September 2026. <https://smartdefine.org/harden/thesaurus/synonyms>