touch-tone

or touch·tone

[ tuhch-tohn ]
/ ˈtʌtʃˌtoʊn /

adjective

of or relating to a tone-dialing system or a push-button phone operating on tone dialing.

noun

(sometimes initial capital letter) a tone-dialing system.
a telephone utilizing this system.

Origin of touch-tone

An Americanism dating back to 1955–60

British Dictionary definitions for touch-tone

touch-tone

adjective

of or relating to a telephone dialling system in which each of the buttons pressed generates a tone of a different pitch, which is transmitted to the exchange