1. to straighten something that was bent or curved
2. to become less formal, strict, or tense in manner or behavior

Examples

• She unbends the wire to make it straight again.
• The metal rod unbends when heated.
• After work, he finally unbends and jokes with his colleagues.
• The strict teacher rarely unbends during class.
• She unbends her knees after sitting for hours.
• The boss unbends at the company picnic and plays games with everyone.