104 entries under hard topic. ×

20
inextricable(adjective, difficult, complicated, complexity)
20
painful(adjective, difficult)
20
tight(adjective, difficult)
19
anfractuous(adjective, difficult)
19
grinding(adjective, difficult)
19
nasty(adjective, difficult)
19
operose(adjective, difficult)
19
tangly(adjective, difficult)
19
weighty(adjective, difficult)
18
impossible(adjective, difficult, number)
18
precarious(adjective, difficult)
17
troubled(adjective, upset, difficult, anxious)
15
convoluted(adjective, simple, fancy, difficult)
14
puzzling(adjective, fancy, difficult, heavy)
12
perplexing(adjective, fancy, difficult, delicate)
11
obscure(adjective, difficult, delicate, heavy)
10
abstruse(noun, adjective, fancy, difficult)
8
ticklish(adjective, difficult, delicate, awkward)
8
subtle(adjective, delicate, heavy, loose)
7
baffling(adjective, difficult, delicate, awkward)
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APASmart Define. (2016). complex thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/complex/thesaurus/synonyms
ChicagoSmart Define. 2016. "complex thesaurus" https://smartdefine.org/complex/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, complex thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/complex/thesaurus/synonyms>.
MLASmart Define. "complex thesaurus" 11 January 2016. Web. 20 September 2026. <https://smartdefine.org/complex/thesaurus/synonyms>