71 entries under hard topic. ×

21
knotted(adjective, difficulty, difficult, complex)
21
precarious(adjective, difficult, complex)
20
burdensome(adjective, difficult, complex)
20
impossible(adjective, difficulty, difficult, complex)
20
labyrinthine(adjective, difficulty, difficult, complex)
20
operose(adjective, difficult, complex)
20
oppressive(adjective, difficult, complex)
20
sore(adjective, difficult, complex)
20
stressful(adjective, difficult, complex)
20
tight(adjective, difficult, complex)
19
Gordian(adjective, difficult, complex, involved)
19
grinding(adjective, difficult, complex)
19
profound(adjective, difficult, complex)
19
sophisticated(adjective, difficult, complex, involved)
19
stubborn(adjective, difficulty, difficult, complex)
18
byzantine(adjective, difficult, complex, involved)
18
elaborate(adjective, difficult, complex, intricate)
18
esoteric(adjective, difficult, complex)
10
troublesome(adjective, rough, difficult, delicate)
8
perplexing(adjective, difficult, delicate, complex)
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APASmart Define. (2015). thorny thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/thorny/thesaurus/synonyms
ChicagoSmart Define. 2015. "thorny thesaurus" https://smartdefine.org/thorny/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2015, thorny thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/thorny/thesaurus/synonyms>.
MLASmart Define. "thorny thesaurus" 13 April 2015. Web. 29 September 2026. <https://smartdefine.org/thorny/thesaurus/synonyms>