95 entries under hard topic. ×

3
fancy(adjective, difficult, complex, sophisticated)
3
mysterious(adjective, obscure, complex, tricky)
2
bewildering(adjective, obscure, sophisticated, tricky)
2
delicate(complex, awkward, tricky, complicated)
2
meandering(obscure, complex, sophisticated, tricky)
2
mystifying(adjective, difficult, awkward, tricky)
2
problematical(adjective, difficult, delicate, loose)
2
ticklish(delicate, awkward, tricky, complicated)
2
troublesome(adjective, fancy, difficult, complex)
2
unfathomable(adjective, obscure, sophisticated, tricky)
1
Daedalean(adjective, fancy, obscure, difficult)
1
abstract(obscure, tricky, complicated, puzzling)
1
can of worms(expression, adjective, idiom, fancy)
1
confounding(adjective, tricky, complicated, puzzling)
1
enigmatical(tricky, complicated, caught, multiplex)
1
formidable(adjective, rough, difficult, complex)
1
gasser(adjective, fancy, difficult, complex)
1
heavy(adjective, tough, obscure, rough)
1
hi-tech(adjective, fancy, difficult, complex)
1
inexplicable(tricky, complicated, perplexing, bewildering)
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APASmart Define. (2015). involved thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/involved/thesaurus/synonyms
ChicagoSmart Define. 2015. "involved thesaurus" https://smartdefine.org/involved/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2015, involved thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/involved/thesaurus/synonyms>.
MLASmart Define. "involved thesaurus" 14 April 2015. Web. 26 September 2026. <https://smartdefine.org/involved/thesaurus/synonyms>