Another word for difficult
Hard to achieve
laborious, hard, arduous, strenuous, demanding, exacting, hard-won, stiff, heavy, painful, labored, trying, titanic, bothersome, troublesome, burdensome, backbreaking, not easy, wearisome, onerous, attended by obstacles, rigorous, Herculean, requiring much effort, Gargantuan, uphill, Sisyphean, challenging, taxing, formidable, ambitious, intricate, irksome, vexatious, tedious, immense, exhausting, grueling, stressful, unyielding, tricky, delicate, ticklish, beyond one's ability, tough*, heavy*, man-sized*, no picnic*, hairy*, sticky*; see also onerous, severe 1.
Hard to understand
intricate, involved, perplexing, abstruse, abstract, tricky, hard, obscure, complex, complicated, knotty, thorny, troublesome, obstinate, puzzling, mysterious, mystifying, subtle, confusing, bewildering, dark, confounding, esoteric, unclear, mystical, tangled, hard to explain, hard to solve, entangled, profound, vexing, baffling, enmeshed, rambling, loose, meandering, trackless, inexplicable, pathless, awkward, digressive, turgid, deep, stubborn, labyrinthine, hidden, formidable, enigmatic, occult, paradoxical, incomprehensible, unintelligible, inscrutable, inexplicable, unanswerable, not understandable, unsolvable, unfathomable, concealed, unaccountable, ambiguous, equivocal, metaphysical, inconceivable, recondite, overtechnical, unknown, steep*, tough*, over one's head*, beyond one's depth*, too deep*, beyond one's comprehension, not making sense, Greek to*, past comprehension; see also obscure 1, 3.
Hard to deal with or manage
hard, in this comparison, is the simple and general word for whatever demands great physical or mental effort hard work, a hard problem; difficult applies especially to that which requires great skill, intelligence, tact, etc. rather than physical labor a difficult situation; a difficult book; arduous implies the need for diligent, protracted effort the arduous fight ahead of us; laborious suggests long, wearisome toil the laborious task of picking fruit
Another word for difficultadjective
Not easy to do, achieve, or master:arduous, hard, laborious, serious, tall, tough, uphill. See easy
Requiring great or extreme bodily, mental, or spiritual strength:arduous, backbreaking, burdensome, demanding, effortful, exacting, exigent, formidable, hard, heavy, laborious, onerous, oppressive, rigorous, rough, severe, taxing, tough, trying, weighty. See heavy
Causing difficulty, trouble, or discomfort:incommodious, inconvenient, troublesome. See comfort
Given to acting in opposition to others:balky, contrarious, contrary, froward, impossible, ornery, perverse, wayward. See attitude, support