How to say "difficulty" in Japanese

• 困難こんなんJLPT N3approx.Common
  noun, na-adjectiveCovers 'difficulty' as an abstract hardship or a trying situation. Use it for serious difficulties facing a task, project, or period of life, often in writing and formal discussion.
  彼かれの言いってる事ことを理解りかいするのは困難こんなんだ。↗

  I found it difficult to understand what he was saying.
• 苦労くろうJLPT N3approx.Common
  noun, suru verb, transitive verb, intransitive verbCovers 'difficulty' as personal trouble and hardship — the toil and effort someone endures. Typical when talking about the hardships of raising children, work, or a difficult life.
  せっかくの苦労くろうもあだになった。↗

  All my pains went for nothing.
• トラブルJLPT N1approx.Common
  nounCovers 'difficulty' in the sense of a concrete problem, mishap, or quarrel — technical trouble, disputes, or trouble between people. A loanword, casual and everyday in feel.
  私はトラブルに巻き込まきこまれた。↗

  I was involved in the trouble.
• 難なんJLPT N1approx.Common
  noun, noun (suffix)Appears in glosses as difficulty, trouble, hardship, or shortage, but it is chiefly a suffix-like element, so as a standalone word it is seldom what you want for 'difficulty'; prefer other entries here.
• 難関なんかんCommon
  nounCovers 'difficulty' as a barrier, obstacle, or hurdle to be overcome — a tough exam, a challenging stage of a plan. It frames the difficulty as something to clear or pass through.
  初はじめの一いち歩ほが唯一ゆいいつの難関なんかん。↗

  The first step is the hardest.

For 'difficulty' as an abstract hardship use 困難; for personal toil use 苦労; for a concrete problem or mishap use 「トラブル」; 難 and 難関 lean toward obstacles and hurdles.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 困難こんなんdifficulty
• 苦労くろうtrouble
• トラブルtrouble
• 難なんdifficulty
• 難関なんかんbarrier
• 難事なんじdifficulty
• 難渋なんじゅうsuffering
• 障害しょうがいobstacle
• 支障ししょうobstacle
• 造作ぞうさtrouble
• 難きかたきdifficulty
• 苦くpain
• 困ったことこまったことtrouble
• 障礙しょうげobstacle
• 難易なんい(relative) difficulty
• 難しさむずかしさ(degree of) difficulty
• 面倒めんどうtrouble
• 狭き門せまきもんhigh barrier (to enter a highly competitive school, company, etc.)
• 壁かべbarrier
• つかえobstacle
• 難儀なんぎsuffering
• 問題もんだいtrouble