autodialer

a telephone device that makes possible a service feature (autodial ) whereby a call is automatically made in response to a brief input signal from the user, as the pressing of a button: I programmed my number into the first memory slot of the autodialer on Grandma’s phone.

a computer program that dials phone numbers from a predetermined or algorithmically derived list, connecting a phone operator with one call after another, as in a telemarketing call center: The autodialer maximizes operators’ efficiency by connecting them only to the calls that are answered.