Crumple and Ruck up

Crumple verb - To create (as by crushing) an irregular mass of creases in.

Ruck up and crumple are semantically related in crease topic. In some cases you can use "Ruck up" instead a verb "Crumple".

Ruck up verb - Become wrinkled or drawn together.

Crumple and ruck up are semantically related in crush topic. You can use "Crumple" instead a verb "Ruck up", if it concerns topics such as twist, fold, wrinkle, scrunch up.