39 entries under secret topic. ×

13
enigma(noun, trouble, informal, challenge, question)
9
mystery(noun, trouble, difficulty, reason, informal)
8
riddle(noun, trouble, challenge, question)
6
mystification(noun, trouble, challenge, question)
6
problem(noun, trouble, challenge, question)
6
puzzlement(noun, trouble, challenge, question)
5
poser(noun, trouble, difficulty, challenge, question)
4
closed book(noun, expression, trouble, challenge, question)
3
perplexity(noun, difficulty, informal, question)
3
question(difficulty, puzzle, obscurity, knot)
2
crux(difficulty, question, puzzle, knot)
2
grabber(noun, information, difficulty, reason, challenge)
2
puzzle(difficulty, question, problem, obscurity)
2
stumper(difficulty, question, puzzle, knot)
2
tough nut to crack(expression, idiom, question, puzzle)
1
abstruseness(difficulty, question, puzzle, obscurity)
1
brainteaser(difficulty, question, puzzle, obscurity)
1
braintwister(difficulty, question, puzzle, obscurity)
1
charade(difficulty, question, puzzle, obscurity)
1
chiller(difficulty, question, puzzle, obscurity)
<12>
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APASmart Define. (2016). why thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/why/thesaurus/synonyms
ChicagoSmart Define. 2016. "why thesaurus" https://smartdefine.org/why/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, why thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/why/thesaurus/synonyms>.
MLASmart Define. "why thesaurus" 2 February 2016. Web. 23 September 2026. <https://smartdefine.org/why/thesaurus/synonyms>