たるむ・弛むtarumu[0]heiban (flat)

1. godan verb, intransitive verbto slacken; to loosen; to relax; to droop (e.g. loose or flabby skin); to sag (ceiling)
2. godan verb, intransitive verbto slack off (e.g. one's work, attention); to not put one's heart in

• Synonym緩むゆるむNeutralBroader word for becoming loose, relaxing, or slacking off. 「弛む」 stresses sagging of ropes or skin; for mental states it usually means slacking off.
• Synonym弛緩しかんWrittenWritten, often medical noun for slackening of muscles, the mind, or discipline, as in 「筋肉の弛緩」「規律の弛緩」. 「弛む」 is the everyday verb.
• Synonym緩まるゆるまるNeutralMeans becoming loose or soft but is rarely used; in daily speech 「緩む」 is the usual word. 「弛む」 stresses sagging or drooping.
• RelatedほぐれるNeutralFor tangles coming undone or tension easing — usually a positive change. When 「弛む」 describes the mind it usually means slacking off.
• RelatedだれるCasualColloquial for going listless or dragging. 「弛む」 stresses physical sagging but also covers mental slacking.
• Antonym張るはるNeutralAntonym: to stretch or tighten, as in 「気を張る」「ロープを張る」 — the opposite of sagging or slacking off.

Use 「弛む」 for ropes or skin sagging and for slacking off, as in 「気が弛む」「皮膚が弛む」. For general loosening or relaxing say 「緩む」; in written or medical prose 「弛緩」; for going listless 「だれる」; the opposite of sagging is 「張る」.

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

1. まっすぐ張はっていた物ものが緩ゆるむ。
2. 気きが緩ゆるみ、だらしなくなる。