cross talk
noun
1.
interference heard on a telephone or radio because of unintentional coupling to another communication channel.
2.
incidental conversation; chatter, as opposed to formal discussion:
The meeting was slowed by cross talk between board members.
3.
British.
witty, fast-paced dialogue, especially in a play, comic act, etc.; repartee.
Also,
cross-talk,
crosstalk
.
Origin
1885-90