TWIDDLE

[verb] [T; I + with] - to move (something) repeatedly between your fingers, esp. without any purposeShe was twiddling (with) the pencil/her hair.Twiddle a dial/knob on a radio in Britain and you may hear more voices speaking crackly French or German than English.If you twiddle your thumbs you do nothing for a period of time, usually while you are waiting for something to happen.He arrived early for the meeting so he had to twiddle his thumbs for half an hour.