Blue Light Definition

Visible light towards the blue end of the spectrum generated from the screen of an electronic device.

A mixture of chemicals (including nitre , sulfur and antimony ) used in eighteenth and nineteenth centuries for pyrotechnics , night-time signaling and general illumination .

A flashing light, usually fitted to an emergency vehicle .

Used other than figuratively or idiomatically: see blue ,‎ light .

To travel quickly in a police or ambulance vehicle with the lightbar (and possibly the siren ) activated.