dialling tone
US and Canadian dial tone
noun
a continuous sound, either purring or high-pitched, heard over a telephone indicating that a number can be dialled
Compare ringing tone, engaged tone
Words nearby dialling tone
dialectology,
dialer,
diallage,
dialled in,
dialling code,
dialling tone,
diallyl sulfide,
dialog box,
dialogic,
dialogism,
dialogist