, Gordian knot, addle, ail, amaze, apply the mind, baffle, bafflement, baffling problem, bamboozle, be the matter, beat, befog, befuddle, beset, bewilder, bewilderment, boggle, bother, brain twister, brain-teaser, buffalo, cap, complicate matters, concern, confound, confoundment, confuse, confusion, consider, contemplate, conundrum, crossword puzzle
, crux, dark horse, daze, decipher, dilemma, discommode, discomposure, disconcert, disconcertedness, disconcertion, disconcertment, distract, distress, disturb, disturbance, dumbfound, embarrassment, enigma, enigmatic question, figure out, fix, flabbergast, floor, floorer, flummox, foil, frontier, frontiers of knowledge, frustrate, fuddle, get, hammer at, hammer away at, harass, inconvenience, irk, jam, jigsaw puzzle
, keep in suspense, knot, knotty point, lick, matter of ignorance, maze, mind-boggler, muddle, mull over, muse on, muse over, mystery, mystification, mystify, n, node, nodus, nonplus, nut to crack, oxymoron, paradox, perplex, perplexed question, perplexity, perturb, perturbation, pickle, plague, plight, ponder over, pons asinorum, pose, poser, pother, predicament, problem, put out, put to it, puzzle
over, puzzlement, puzzler, quandary, question, question mark, reflect over, riddle, scrape, sealed book, sixty-four dollar question, solve, sort out, stew, stew over, stick, sticker, study, stumble, stump, stumper, stymie, teaser, terra incognita, the incalculable, the strange, the unfamiliar, the unknowable, the unknown, think hard, think through, throw, torment, tough proposition, trouble, unassuredness, unexplored ground, unexplored territory, unknown quantity, unlock, unravel, upset, vex, vexed question, why, work out, worry, x, z
difficulty, hardness, impracticability, tough work, hard work, uphill work, hard task, Herculean task, Augean task, task of Sisyphus, Sisyphean labor, tough job, teaser, rasper, dead lift, dilemma, embarrassment, deadlock, perplexity, intricacy, entanglement, complexity, cross fire, awkwardness, delicacy, ticklish card to play, knot, Gordian knot, dignus vindice nodus, net, meshes, maze, coil, crooked path, involvement, nice point, delicate point, subtle point, knotty point, vexed question, vexata quaestio, poser, puzzle
, paradox, hard nut to crack, nut to crack, bone to pick, crux, pons asinorum, where the shoe pinches, nonplus, quandary, strait, pass, pinch, pretty pass, stress, brunt, critical situation, crisis, trial, rub, emergency, exigency, scramble, scrape, hobble, slough, quagmire, hot water, hornet's nest, sea of troubles, peck of troubles, pretty kettle of fish, pickle, stew, imbroglio, mess, ado, false position, set fast, stand, standstill, deadlock, dead set, fix, horns of a dilemma, cul de sac, hitch, stumbling block, crab, curmudgeon, difficult, not easy, hard, tough, troublesome, toilsome, irksome, operose, laborious, onerous, arduous, Herculean, formidable, sooner said than done, more easily said than done, easier said than done, difficult to deal with, hard to deal with, ill-conditioned, crabbed, crabby, not to be handled with kid gloves, not made with rose water, awkward, unwieldy, unmanageable, intractable, stubborn, perverse, refractory, plaguy, trying, thorny, rugged, knotted, knotty, invious, pathless, trackless, labyrinthine, intricate, complicated, impracticable, not feasible, desperate, embarrassing, perplexing, delicate, ticklish, critical, beset with difficulties, full of difficulties, surrounded by difficulties, entangled by difficulties, encompassed with difficulties, under a difficulty, in a box, in difficulty, in hot water, in the suds, in a cleft stick, in a fix, in the wrong box, in a scrape, in deep water, in a fine pickle, in extremis, between two stools, between Scylla and Charybdis, surrounded by shoals, surrounded by breakers, surrounded by quicksands, at cross purposes, not out of the wood, reduced to straits, hard pressed, sorely pressed, run hard, pinched, put to it, straitened, hard up, hard put to it, hard set, put to one's shifts, puzzled, at a loss, at the end of one's tether, at the end of one's rope, at one's wit's end, at a nonplus, at a standstill, graveled, nonplused, nonplussed, stranded, aground, stuck fast, set fast, up a tree, at bay, aux abois, driven into a corner, driven from pillar to post, driven to extremity, driven to one's wit's end, driven to the wall, au bout de son Latin, out of one's depth, thrown out, accomplished with difficulty, hard-fought, hard-earned, with difficulty, with much ado, barely, hardly, uphill, against the stream, against the grain, d rebours, invita Minerva, in the teeth of, at a pinch, upon a pinch, at long odds, against long odds, ay there's the rub, hic labor hoc opus, things are come to a pretty pass, ab inconvenienti, ad astra per aspera, acun chemin de fleurs ne conduit a la gloire.
be uncertain, wonder whether, lose the clue, lose the clew, scent, miss one's way, not know what to make of, not know which way to turn, not know whether one stands on one s head or one's, float in a sea of doubt, hesitate, flounder, lose oneself, lose one's head, muddle one's brains, render uncertain, put out, pose, puzzle
, perplex, embarrass, confuse, confound, bewilder, bother, molder, addle the wits, throw off the scent, ambiguas in vulgus spargere voces, keep in suspense, doubt, hang in the balance, tremble in the balance, depend.
unintelligibility, incomprehensibility, imperspicuity, inconceivableness, vagueness, obscurity, ambiguity, doubtful meaning, uncertainty, perplexity, spinosity, obscurum per obscurius, mystification, latency, transcendentalism, paradox, oxymoron, riddle, enigma, puzzle
, diagnus vindice nodus, sealed book, steganography, freemasonry, pons asinorum, asses' bridge, high Dutch, Greek, Hebrew, jargon, unintelligible, unaccountable, undecipherable, undiscoverable, unknowable, unfathomable, incognizable, inexplicable, inscrutable, inapprehensible, incomprehensible, insolvable, insoluble, impenetrable, illegible, as Greek to one, unexplained, paradoxical, enigmatic, enigmatical, puzzling (secret), indecipherable, obscure, dark, muddy, clear as mud, seen through a mist, dim, nebulous, shrouded in mystery, opaque, dense, undiscernible, misty, hidden, latent, indefinite, garbled, perplexed, undetermined, vague, loose, ambiguous, mysterious, mystic, mystical, acroamatic, acroamatical, metempirical, transcendental, occult, recondite, abstruse, crabbed, inconceivable, inconceptible, searchless, above comprehension, beyond comprehension, past comprehension, beyond one's depth, unconceived, inexpressible, undefinable, incommunicable, unpredictable, unforeseeable, it's Greek to me.
conceal, hide, secrete, put out of sight, lock up, seal up, bottle up, encrypt, encode, cipher, cover, screen, cloak, veil, shroud, cover up one's tracks, screen from sight, screen from observation, drawing the veil, draw the curtain, close the curtain, curtain, shade, eclipse, throw a view over, be cloud, be mask, mask, disguise, ensconce, muffle, smother, befog, whisper, keep from, keep back, keep to oneself, keep snug, keep close, keep secret, keep dark, bury, sink, suppress, keep from, keep from out of view, keep from out of sight, keep in the shade, throw into the shade, throw into background, stifle, hush up, smother, withhold, reserve, fence with a question, ignore, keep a secret, keep one's own counsel, hold one's tongue, make no sign, not let it go further, not breathe a word, not breathe a syllable about, not let the right hand know what the left is doing, hide one's light under a bushel, bury one's talent in a napkin, keep in the dark, leave in the dark, keep in the ignorance, blind, blind the eyes, blindfold, hoodwink, mystify, puzzle
, bamboozle, be concealed, suffer an eclipse, retire from sight, couch, hide oneself, lie hid, lie in perdu, lie in close, lie in ambush (ambush), seclude oneself, lurk, sneak, skulk, slink, prowl, steal into, steal out of, steal by, steal along, play at bopeep, play at hide and seek, hide in holes and corners, still hunt.
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.