nounNorth American informal
A warning light that goes on when a fault occurs in a device.
More example sentences
- The idiot light for Foxtrot Base just turned red; they are surrounded.
- For providing an easy-to-use ‘security idiot light’ to Linux system administrators and distributions everywhere, Nmap, we salute you.
- Other than this high-tech version of a car's idiot light, I saw no other symptoms.
Definition of idiot light in:
- The US English dictionary