blue light

Meanings

1. A mixture of chemicals (including nitre, sulfur and antimony) used in the eighteenth and nineteenth centuries for night-time signaling and general illumination.
2. A New England federalist, who opposed the Anglo-American War of 1812; (loosely), a federalist.
3. A flashing light, usually fitted to an emergency vehicle.
4. Used other than figuratively or idiomatically: see blue, light.

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