| fussbudget(adjective, rough, careful, thorough, demanding) |
| industrious(adjective, thorough, meticulous, painstaking) |
| problem(noun, difficulty, challenge, question, secret) |
| punctilious(adjective, thorough, meticulous, painstaking) |
| riddle(noun, difficulty, challenge, question, problem) |
| scrupulous(adjective, thorough, meticulous, painstaking) |
| tyrant(noun, severity) |
| closed book(expression, difficulty, question, secret, puzzle) |
| conscionable(adjective, thorough, meticulous, painstaking) |
| contender |
| cryptogram(difficulty, question, secret, puzzle, knot) |
| earnest(adjective, thorough, meticulous, painstaking) |
| enthusiast |
| exacting(adjective, rough, careful, thorough, demanding) |
| fussy(adjective, careful, thorough, meticulous, fastidious) |
| grabber(noun, difficulty, challenge, question, problem) |
| hard-working(adjective, thorough, meticulous, painstaking) |
| harpy(noun, severity) |
| heedful(adjective, thorough, meticulous, painstaking) |
| inquisitor(noun, severity) |