66 entries under complex topic. ×

19
painful(adjective, hard, difficult)
19
problematic(adjective, hard, difficult)
19
sensitive(adjective, hard, difficult, subtle)
19
toilsome(adjective, hard, difficult)
19
unbearable(adjective, hard, difficult)
18
sad(adjective, hard, difficult, greatness)
18
dire(adjective, hard, difficult)
18
labyrinthine(adjective, hard, difficult)
18
leaden(adjective, hard, difficult)
18
massive(adjective, hard, difficult)
18
ponderous(adjective, hard, difficult)
18
sheer(adjective, hard, difficult)
11
obscure(adjective, hard, deep, mysterious)
10
subtle(adjective, quiet, hard, slight, fine)
9
mysterious(adjective, hard, obscure, delicate)
8
arcane(adjective, obscure, deep, mysterious)
7
occult(adjective, obscure, deep, thoughtful)
7
scholarly(adjective, obscure, smart, bright)
6
hidden(hard, obscure, deep, cunning)
3
hermetic(adjective, obscure, deep, thoughtful)
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APASmart Define. (2016). profound thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/profound/thesaurus/synonyms
ChicagoSmart Define. 2016. "profound thesaurus" https://smartdefine.org/profound/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, profound thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/profound/thesaurus/synonyms>.
MLASmart Define. "profound thesaurus" 26 February 2016. Web. 21 September 2026. <https://smartdefine.org/profound/thesaurus/synonyms>