207 entries under hard topic. ×

5
solidified(adjective, set, solid, heavy)
4
austere(adjective, strong, tough, severe)
4
cemented(adjective, set, strong, secure)
4
compacted(adjective, set, strong, solid)
4
congealed(adjective, set, solid, heavy)
4
jelled(adjective, set, solid, heavy)
4
nonporous(adjective, solid, rigid, inflexible)
4
packed(adjective, close, set, strong)
4
physical(adjective, strong, solid, material)
4
rocklike(adjective, strong, substantial, stiff)
4
serious(adjective, strong, tough, severe)
4
stiff-necked(adjective, mean, strong, tough)
3
authoritarian(adjective, strong, tough, severe)
3
bullheaded(adjective, strong, tough, determined)
3
exacting(adjective, tough, severe, rough)
3
hard-line(adjective, strong, tough, severe)
3
hard-shelled(adjective, tough, severe, rough)
3
hardheaded(adjective, strong, tough, determined)
3
husky(adjective, strong, tough, fit)
3
material(adjective, strong, solid, physical)
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APASmart Define. (2016). firm thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/firm/thesaurus/synonyms
ChicagoSmart Define. 2016. "firm thesaurus" https://smartdefine.org/firm/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, firm thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/firm/thesaurus/synonyms>.
MLASmart Define. "firm thesaurus" 31 March 2016. Web. 25 September 2026. <https://smartdefine.org/firm/thesaurus/synonyms>