一生懸命|いっしょうけんめいisshoukenmei[5]nakadaka (mid-high)

1. adverb, na-adjective, nounvery hard; with utmost effort; as hard as one can; with all one's might; for dear life; eagerly; desperately
   もっと一生懸命いっしょうけんめい勉強べんきょうすべきだったのに。↗

   You should have worked harder.

• Synonym懸命けんめいNeutralAlso 'with all one's effort', as in 「懸命な捜索」 or 「懸命に努力する」, but more formal than 「一生懸命」 and common in news reports.
• SynonymひたすらWrittenWritten word for doing one thing single-mindedly, as in 「ひたすら謝る」; stresses keeping at just that one action and nothing else.
• Related真面目まじめNeutralDescribes a serious, steady character or attitude, as in 「真面目な学生」; it is about the person's makeup, not the intensity of effort.
• Related本気ほんきNeutralMeans being in earnest, not joking, as in 「本気で怒る」; the point is that you mean it, not how much effort you put in.
• Related真摯しんしWrittenWritten word for sincere, earnest feeling, as in 「真摯に受け止める」; used mostly in formal statements.
• Related真剣しんけんNeutralSignals taking something seriously, not half-heartedly, as in 「真剣に考える」 or 「真剣な顔」; about the earnest attitude, not exerting all one's strength.
• Related一途いちずWrittenDevoted and unwavering, as in 「一途な恋」; used mostly for love, feelings or convictions, stressing that one never changes course.
• Related丹念たんねんWrittenWritten word for doing something patiently and painstakingly, as in 「丹念に調べる」; stresses fine care, not the amount of effort.
• Related入念にゅうねんWrittenWritten word for extra-careful, thorough attention, as in 「入念な準備」; stresses leaving nothing overlooked, not hard striving.
• Related念入りねんいりNeutralCareful and thorough in method, as in 「念入りに掃除する」; about doing a task meticulously without cutting corners, not about effort.
• RelatedシリアスCasualLoanword for grave and serious, as in 「シリアスな話」; describes an atmosphere or a work (film, story), not the degree of effort.
• Related熱心ねっしんNeutralEager and enthusiastic involvement, as in 「熱心に勉強する」; stresses zeal and energy, but does not necessarily mean giving everything.
• Related一筋ひとすじWrittenWritten word for sticking to one thing alone, as in 「仕事一筋」; stresses years of devotion to a single path, not a burst of effort.
• RelatedひたむきWrittenWritten word for single-minded devotion to one thing, as in 「ひたむきな努力」; carries a moving, heartfelt nuance of focusing on one goal alone.
• Related生真面目きまじめNeutralOverly serious and inflexible, as in 「生真面目な性格」; carries a hint of rigidity and describes a personality rather than effort.
• Related熱誠ねっせいWrittenWritten word for ardent sincerity of feeling, as in 「熱誠を込めて」; fairly rare; stresses the warmth of one's heart, not exertion.
• Antonym怠惰たいだWrittenAntonym of 「一生懸命」: written word for laziness and idleness, as in 「怠惰な生活」.
• Antonym不真面目ふまじめNeutralAntonym: not serious, half-hearted or frivolous, as in 「不真面目な態度」.

Default to 「一生懸命」 for striving with all one's might. Use 「懸命」 in formal contexts such as news; 「真面目」 or 「真剣」 for being serious, 「本気」 for meaning it; 「ひたむき」 or 「一途」 for single-minded devotion. The opposite is 「怠惰」.

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

1. 命懸いのちがけで。