1. the action or process of becoming wrinkled, folded, or crushed
Usage: gerund form

1. present participle of crumple; crushing or wrinkling something into folds
Usage: present participle form

Examples

• She was crumpling the paper into a ball.
• The crumpling of the metal showed the force of impact.
• He heard the crumpling sound of leaves underfoot.
• The fabric was crumpling in her hands.
• The crumpling of his face showed his disappointment.
• She watched him crumpling the letter in frustration.