rumple
     v 1: disturb the smoothness of; "ruffle the surface of the water"
          [syn: {ruffle}, {ruffle up}, {mess up}]
     2: to gather something into small wrinkles or folds; "She
        puckered her lips" [syn: {pucker}, {cockle}, {crumple}, {knit}]
     3: become wrinkled or crumpled or creased; "This fabric won't
        wrinkle" [syn: {crumple}, {wrinkle}, {crease}, {crinkle}]
Source: WordNet® 2.0