| secrecy(difficulty, question, secret, puzzle, obscurity) |
| secret(question, problem, puzzle, obscurity, knot) |
| seriously |
| sixty-four-thousand-dollar question(expression, difficulty, question, secret, puzzle) |
| sixty-four dollar question(expression, idiom) |
| skinny(noun, information, reason, picture, evidence) |
| smoking gun(noun, expression, information, reason, picture) |
| sole |
| sphinx(difficulty, question, secret, puzzle, knot) |
| stated cause |
| sticker |
| stickler(difficulty, question, secret, puzzle, knot) |
| straight stuff(noun, expression, information, cause, reason) |
| substantiation(noun, information, reason, picture, evidence) |
| subtlety(difficulty, question, secret, puzzle, obscurity) |
| target(noun, cause, purpose, basis, planned) |
| teaser(difficulty, question, secret, puzzle, knot) |
| testament(noun, information, reason, picture, evidence) |
| testimony(noun, information, cause, reason, base) |
| thriller(difficulty, question, secret, puzzle, obscurity) |