A baby monitor is the device that lets you hear a sleeping baby. Switch on the baby monitor.
It transmits every breath, which reassures some parents and keeps others awake. A baby monitor on a network can be watched by anybody if the password is left as it came.
1nounbaby monitorThe device that lets you hear a sleeping baby.
“The baby monitor picked up the neighbour's television all evening.”
baby monitor is a device.
Practised in Babies & Growing Up