call-waiting
call-wait·ing [ ˈkȯl-ˈwā-tiŋ]
[ˈkȯl-ˈwā-tiŋ]
: a telephone service that signals (as by a beep) to the user when an incoming call is received during a call in progress
First Known Use of call-waiting
1963, in the meaning defined above
Dictionary Entries near call-waiting