Synonyms for Difficulty:

n.

rigorousness. under a handicap, having a hard time, having a bad time. easy, asperity. hot spot, box, spot, soup, dutch. war, contention, faction, schism, disaccord, discord, dissentience, dissent, dissidence, variance, friction, conflict, Inharmony, confrontation, difference, dissonance, warfare, dissension, discordance, clash. word, spat, argument, polemic, tangle, bicker, disagreement, altercation, run-in, quarrel, debate, wrangle, rhubarb, controversy, squabble, dispute, fight, tiff. act (noun)
trouble.
adversity (noun)
distress, hard times, catastrophe, misfortune, woe, mishap, adversity, tragedy, grief, trouble, hard luck, bad luck, destitution, agony, poorness, rainy day, dolor, trial, infliction, misery, contretemps, calamity, poverty, affliction, burden, bane, peril, ordeal, misadventure, hardship, curse, blight, torment, disaster, tribulation, casualty.
aggravation (noun)
headache.
argument (noun)
dispute, controversy, quarrel, squabble, altercation, fight.
complexity (noun)
intricacy, Cabalism, subtlety, entanglement, mystery, complexity, convolution, abstruseness, obscurity, puzzle.
crisis (noun)
dilemma.
difficulty (noun)
onerousness, trickiness, difficultness, oppressiveness, harshness, cantankerousness, strenuousness, hardness, toughness, severity, roughness, complication, knottiness, contrariness, trouble, fussiness, ticklishness, wearying, tightness, cumbersomeness, muddle, corner, stressfulness, arduousness, wearisomeness, formidability.
disagreement (noun)
quarrel.
disappointment (noun)
setback, frustration.
hang-up (noun)
hang up.
hindrance (noun)
stumbling block, setback.
mental burden (noun)
aggravation, vicissitude, responsibility, jam, annoyance, setback, irritation, strife, to-do, care, oppression, puzzle, pinch, pressure, grievance, inconvenience, discouragement, harassment, maze, depression, millstone, ado, embarrassment, weight, misery, anxiety, charge, stress.
millstone (noun)
millstone.
objection (noun)
objection, demur, unwillingness, reluctance, flak.
pitfall (noun)
quicksand.
predicament (noun)
perplexity, predicament, dilemma, plight, quandary, pickle, fix, problem, jam.
problem; situation requiring great effort (noun)
strenuousness, perplexity, adversity, dilemma, scrape, quandary, stumbling block, deadlock, frustration, complication, impasse, exigency, emergency, distress, pain, muddle, trouble, arduousness, hardship, hazard, fix, predicament, crisis, paradox, snag, pickle, stew, struggle, check, barricade, misfortune, mess, hot water, deep water, tribulation, knot, strain, quagmire, hitch.

Other synonyms:

nuisance, stumbling block, dissentience, deep water, toughie, dutch, snag, exigency, fight, rhubarb, discordance, hot spot, run-in, Inharmony. dissidence, box, debate, quagmire, polemic, headache, friction, millstone, dissonance, challenge, quarrel, dissension, controversy, baggage, hitch, disadvantage, soup, disturbance, annoyance, tiff, rub, hot water, strain, altercation, aggravation. disagreement, spat, care, schism, variance, issue, contention, strife, disaccord. discord, wrangle, warfare, confrontation, faction, catch, conflict, argument, scrape, war. spot, dispute. bind. difference. word. accident
emergency.
bother
inconvenience.
hardship
asperity.
mutability
vicissitude.
problem
hang up.
rigidity
rigor.

Usage examples for difficulty

  1. Clearing's my only difficulty – Foe-Farrell by Arthur Thomas Quiller-Couch