Source : Webster's Revised Unabridged Dictionary (1913)

Tousle \Tou"sle\, v. t. [Freq. of touse. Cf.{Tossle}.]
   To put into disorder; to tumble; to touse. [Colloq.]

Source : WordNet®

tousle
     v : disarrange or rumple; dishevel; "The strong wind tousled my
         hair" [syn: {dishevel}, {tangle}]