How to say "purposely" in Japanese

• あえてJLPT N1approx.Common
  adverbFor purposely doing something needless, unexpected, or seemingly counterproductive — deliberately taking the harder course when an easier one exists, with a nuance of daring to go against expectations.
  あえて彼かれの意見いけんを支持しじした。↗

  I dared to support his opinion.
• 故意にこいに
  adverbThe straightforward 'deliberately, intentionally, on purpose' word: plain intent, with no nuance of doing something unexpected or against the grain. As a less common word, you will more often recognize it than produce it.
  それは偶然ぐうぜんだったのか、それとも故意こいにであったのか。↗

  Was it by accident or by design?

Choose 「あえて」 when the purposeful act is needless, unexpected, or seemingly counterproductive; choose 「故意に」 for plain 'on purpose' intent, though it is the less common of the two.

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

• あえてpurposely (of something needless, unexpected or seemingly counterproductive, etc.)
• 故意にこいにdeliberately