43 entries under hard topic. ×

26
condensed(verb, adjective, set, tough)
20
compact(adjective, set, tough, firm)
16
solid(adjective, set, tough, firm)
15
close(adjective, set, tough, slight)
14
concentrated(verb, adjective, set, tough)
12
dense(adjective, set, tough, firm)
11
compacted(verb, adjective, set, strong)
9
firm(adjective, set, solid, heavy)
9
packed(verb, adjective, close, set, strong)
8
impenetrable(adjective, set, tough, firm)
8
thick(adjective, close, set, tough)
5
stiff(adjective, set, tough, firm)
4
concrete(adjective, set, tough, firm)
4
heavy(adjective, set, tough, solid)
4
rigid(adjective, set, strong, tough)
3
inflexible(adjective, set, strong, tough)
3
solidified(verb, adjective, set, tough)
3
unyielding(adjective, set, tough, firm)
2
hardened(verb, adjective, set, strong)
2
impermeable(adjective, set, tough, firm)
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APASmart Define. (2016). compressed thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/compressed/thesaurus/synonyms
ChicagoSmart Define. 2016. "compressed thesaurus" https://smartdefine.org/compressed/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, compressed thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/compressed/thesaurus/synonyms>.
MLASmart Define. "compressed thesaurus" 26 February 2016. Web. 21 September 2026. <https://smartdefine.org/compressed/thesaurus/synonyms>