[count] 1 a : the part of a clock or watch that has the numbers on it
▪ a clock with a shiny silver dial [=face] — see also sundial
b : the part of a piece of equipment that shows the measurement of something with a moving piece (such as a needle) that points to a number
▪ the dial of a pressure gauge 2 : a round part on a piece of equipment that you turn to operate something: such as a : a round control on a radio or television that you use to select a station or channel or to make the volume louder or quieter
▪ I had to keep adjusting the radio dial to make the station come in clearly. ▪ We'll be back right after this commercial, so don't touch that dial! [=don't change the channel/station]
b : a round part of some telephones that you move to select numbers