真剣|しんけんshinken[0]heiban (flat)

1. na-adjectiveserious; earnest
   ジョージは勉強べんきょうに真剣しんけんでない。↗

   George is not serious about his study.
2. nounreal sword (as opposed to a wooden practice weapon)
   「親父おやじこれって・・・真剣しんけん？」「当たり前あたりまえだろう、決闘けっとうなのだからな」↗

   "Dad, this a real sword?" "Of course, it is a duel after all."

• Synonym真面目まじめNeutralDescribes a person who is earnest and honest by nature — a matter of character. 「真剣」 is about devoting yourself wholeheartedly to something and not joking.
• Synonym本気ほんきNeutralBeing in earnest rather than joking, as in 「本気で怒る」. 「真剣」 stresses a grave, focused attitude.
• Synonym真摯しんしWrittenWritten/formal prose for sincerity and earnestness, often in 「真摯に受け止める」. 「真剣」 is the more colloquial choice.
• SynonymシリアスNeutralA loanword for grave or heavy, mostly describing a story's plot or an atmosphere. 「真剣」 describes a person's attitude.
• Related熱心ねっしんNeutralEnthusiastic dedication to something, as in 「勉強熱心」. 「真剣」 stresses taking things seriously.
• Related一途いちずNeutralSingle-minded devotion, often to a feeling or person, as in 「一途な恋」. 「真剣」 stresses earnestness.
• Related一生懸命いっしょうけんめいNeutralGoing all out, putting everything you have into it. 「真剣」 stresses a serious attitude rather than effort.
• Related熱意ねついNeutralA noun for zeal or enthusiasm. 「真剣」 describes the attitude itself.
• Related熱血ねっけつNeutralHot-blooded passion and fervor, as in 「熱血教師」. 「真剣」 stresses earnestness.
• Related懸命けんめいNeutralStraining every effort, as in 「懸命の努力」. 「真剣」 stresses the attitude rather than the effort.
• Related生真面目きまじめNeutralImplies being serious to excess — earnest but rigid and inflexible. 「真剣」 carries no nuance of rigidity.
• Related意欲的いよくてきNeutralProactive and motivated, eager to take things on. 「真剣」 stresses taking things seriously.
• Antonym冗談じょうだんNeutralStands at the opposite pole from 「真剣」 in seriousness: a joke or jest.
• Antonym遊びあそびNeutralAlso the opposite of 「真剣」 in seriousness: play or amusement rather than earnest purpose.

Use 「真剣」 for a serious, wholehearted attitude toward something. Pick 「本気」 for being in earnest rather than joking, 「真面目」 for an earnest, honest character, 「真摯」 in formal prose for sincerity, and 「一生懸命」 for all-out effort. The rest add shades of enthusiasm, devotion, effort, gravity or rigidity; 「冗談」 and 「遊び」 are the opposites.

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

1. 実際じっさいに戦闘せんとうで使つかう刀かたな。
2. 何なんかを本気ほんきでしようとする様子ようす。