こわばる・強張るkowabaru[3]nakadaka (mid-high)

1. godan verb, intransitive verbto stiffen; to become stiff; to harden

• Synonym硬直こうちょくWrittenWritten/formal prose: rigidity and immobility, of a body or of a system, as in 「死後硬直」; more objective in tone than 「強張る」.
• Synonym固くなるCasualColloquial and general: materials, food, the body — anything can 「固くなる」. When you're tense, 「体が固くなる」 works too; 「強張る」 is about a body or face tensing up.
• Related硬化こうかWrittenWritten/formal prose: hardening of substances or of attitudes, as in 「動脈硬化」 — more objective than 「強張る」.
• Related強直きょうちょくWrittenWritten/formal prose: a medical term for rigidity of the joints and muscles; it can also describe an upright, unbending character.
• Antonym緩むゆるむNeutralNeutral: a taut or tense state 「緩む」 — it loosens or relaxes. The direct opposite of the stiffening of 「強張る」.
• AntonymたるむNeutralThe same word as 「緩む」, also written 「弛む」: an expression or one's guard relaxes. Again the opposite of 「強張る」.
• Antonym和らぐやわらぐNeutralNeutral: to soften and grow gentle or mild — the opposite of the rigidity of 「強張る」.

Use 「強張る」 when a body or expression stiffens with tension or cold, as in 「顔が強張る」 or 「肩が強張る」. For things hardening in general, say 「固くなる」; in written prose, 「硬直」 describes a body going rigid. The opposites are 「緩む」 and 「和らぐ」.

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

1. 柔やわらかいものが固かたく突っ張つっぱる。
2. 顔かおや表情ひょうじょうが硬かたくなる。