Chinese puzzle, ado, aggravation, annoyance, anxiety, bad news, baffle, bafflement, baffling problem
, basis, bedevilment, besetment, bewilderment, blemish, bone of contention, bore, bother, botheration, bothersomeness, brain twister, bug, bugaboo, bugbear, burden, can of worms, case, catch, catechism, chapter, complication, concern, confoundment, confusion, conundrum, count, crack, crashing bore, cross-interrogatory, cross-question, crossword puzzle, crux, debating point, defect, defection, deficiency, delinquent, demand, devilment, difficult, difficulty, dilemma, disadvantage, discomposure, disconcert, disconcertedness, disconcertion, disconcertment, disturbance, disturbed, dogging, downer, drag, drawback, embarrassment, enigma, enigmatic question, essence, evil, exasperation, facer, failing, failure, fault, faute, feeler, fix, flaw, floorer, focus of attention, focus of interest, foible, frailty, gist, great ado, harassment, harrying, head, headache, heading, hole, hounding, illustration, imbroglio, imperfection, inadequacy, inconvenience, incorrigible, infirmity, inquiry, interrogation, interrogative, interrogatory, intractable, issue, jam, jigsaw puzzle, kink, knot, knotty point, leader, leading question, little problem
, living issue, main point, maladjusted, matter, matter in hand, meat, mess, mind-boggler, molestation, moot point, motif, motive, muddle, mystery, nonplus, nuisance, nut, nut to crack, obstreperous, peck of troubles, perplexed question, perplexity, persecution, perturbation, pest, pickle, plight, point, point at issue, point in question, poser, pother, predicament, pretty pickle, puzzle, puzzlement, puzzler, quandary, query, question, question at issue, question mark, quodlibet, refractory, riddle, rift, rubric, scrape, sea of troubles, shortcoming, sixty-four dollar question, snag, something missing, stew, sticker, stumper, subject, subject matter, subject of thought, substance, taint, text, theme, topic, tough proposition, trial, trial balloon, trouble, unassuredness, uncontrollable, ungovernable, unmanageable, unruly, upset, vexation, vexatiousness, vexed question, vulnerable place, weak link, weak point, weakness, why, worriment, worry
topic, subject of thought, material for thought, food for the mind, mental pabulum, subject, subject matter, matter, theme, noemata, topic, what it is about, thesis, text, business, affair, matter in hand, argument, motion, resolution, head, chapter, case, point, proposition, theorem, field of inquiry, moot point, problem
, thought of, uppermost in the mind, in petto, under consideration, in question, in the mind, on foot, on the carpet, on the docket, on the tapis, relative to.
inquiry, request, search, research, quest, pursuit, examination, review, scrutiny, investigation, indagation, perquisition, perscrutation, pervestigation, inquest, inquisition, exploration, exploitation, ventilation, sifting, calculation, analysis, dissection, resolution, induction, Baconian method, strict inquiry, close inquiry, searching inquiry, exhaustive inquiry, narrow search, strict search, study, scire facias, ad referendum, trial, questioning, interrogation, interrogatory, interpellation, challenge, examination, cross-examination, catechism, feeler, Socratic method, zetetic philosophy, leading question, discussion, reconnoitering, reconnaissance, prying, espionage, espionnage, domiciliary visit, peep behind the curtain, lantern of Diogenes, question, query, problem
, desideratum, point to be solved, porism, subject of inquiry, field of inquiry, subject of controversy, point in dispute, matter in dispute, moot point, issue, question at issue, bone of contention, plain question, fair question, open question, enigma, knotty point, quodlibet, threshold of an inquiry, inquirer, investigator, inquisitor, inspector, querist, examiner, catechist, scrutator scrutineer scrutinizer, analyst, quidnunc, inquiry, inquisitive, requisitive, requisitory, catechetical, inquisitorial, analytic, in search of, in quest of, on the lookout for, interrogative, zetetic, all searching, undetermined, untried, undecided, in question, in dispute, in issue, in course of inquiry, under discussion, under consideration, under investigation, sub judice, moot, proposed, doubtful, quaere?, what?, why?, wherefore?, whence?, whither?, where?, how comes it?, how happens it?, how is it?, what is the reason?, what's the matter?, nicht wahr?, what's in the wind?, what on earth?, when?, who?.
secret, dead secret, profound secret, arcanum, mystery, latency, Asian mystery, sealed book, secrets of the prison house, le desous des cartes, enigma, riddle, puzzle, nut to crack, conundrum, charade, rebus, logogriph, monogram, anagram, Sphinx, crux criticorum, maze, labyrinth, Hyrcynian wood, intricacy, meander, problem
, paradox, unintelligibility, terra incognita, secret, involved, labyrinthine, labyrinthian, mazy, confidential, top secret.