2
concentrate(verb, develop, secure, join, unite)
2
condense(verb, form, set, develop, secure)
2
condition(verb, prepare, endure, adjust, familiarize)
2
connect(verb, place, set, meet, develop)
2
contract(verb, close, set, settle, firm)
2
cure(noun, verb, preserve, cook, smoke)
2
dull(verb, thicken, stabilize, toughen, season)
2
endure(verb, keep, overcome, prepare, resist)
2
enure
2
establish(verb, support, place, set, increase)
2
form(verb, set, develop, firm, combine)
2
gelatinize(verb, form, set, fix, develop)
2
hook up with(verb, expression, idiom, meet, develop)
2
jelly(verb, form, set, develop, combine)
2
lapidify(clarify, solidify)
2
league(verb, meet, develop, secure, join)
2
make it(expression, endure, resist, suffer, withstand)
2
orientate(verb, adjust, familiarize, accustom)
2
paralyze(verb, thicken, stabilize, toughen, season)
2
precipitate(verb, close, set, settle, firm)
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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>