Definition of "Dial" :
noun: the face of a timepiece; graduated to show the hours
noun: a disc on a telephone that is rotated a fixed distance for each number called
noun: the circular graduated indicator on various measuring instruments
noun: the control on a radio or television set that is used for tuning
verb: choose by means of a dial
"Dial a telephone number."
verb: operate a dial to select a telephone number
"You must take the receiver off the hook before you dial."