crumple  verb
 to (cause to) become full of irregular folds
 You'll crumple that suit if you don't pack it properly. [T]
 The side of the car had crumpled where it had been hit. [I]
 Sylvie crumpled up the letter and threw it in the bin. [T]

 If someone's face crumples, it becomes full of lines because of a strong emotion.
 His face crumpled and he started to cry.
 Her face crumpled with laughter.

 If someone crumples, they fall to the ground suddenly.
 When he heard the news, he crumpled into a heap on the floor.

 (British and Australian) A crumple zone is a part of a car that is designed to crumple easily in
 an accident and so protect the people inside from being hit too hard.
 The car has front and rear crumple zones and two side-impact protection bars.