本分|ほんぶんhonbun[1]atamadaka (head-high)

1. nounone's duty; one's part
   彼かれは自分じぶんの本分ほんぶんを踏み外ふみはずしたことがない。↗

   He has never swayed from his duty.

• Synonym責務せきむFormalA formal word for obligations one must fulfill under one's responsibility; solemn in tone, stressing how weighty they are. 「本分」 is what one ought to do by one's station.
• Synonym職分しょくぶんWrittenThe duties proper to one's post; a rare, written-style word. 「本分」 is broader, also covering the duties of a student or child, as in 「学生の本分」.
• Related職務しょくむNeutralThe work and tasks one is charged with at a post, with emphasis on concrete duties; often in 「職務を怠る」. Neutral in register.

Use 「本分」 for what one should do by virtue of one's station, as in 「学生の本分」. For the concrete duties of a job or post, choose 「職務」; for weighty responsibilities, the formal 「責務」. 「職分」 is a rare written-style word for post duties.

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

1. 本来ほんらいの地位ちい、本来ほんらい具そなわっている分限ぶんげん。
2. 身みに具そなわっている分ぶん際さい、その人ひとの尽つくすべき義務ぎむ。