1. (

• crumble ,
• crumple ,
• tumble ,
• break_down ,
• collapse ,

) fall apart; "the building crumbled after the explosion"; "Negotiations broke down" ;

2. (

• buckle ,
• crumple ,

) fold or collapse; "His knees buckled" ;

3. (

• pucker ,
• rumple ,
• cockle ,
• crumple ,
• knit

) to gather something into small wrinkles or folds; "She puckered her lips" ;

4. (

• rumple ,
• crumple ,
• wrinkle ,
• crease ,
• crinkle ,

) become wrinkled or crumpled or creased; "This fabric won't wrinkle" ;