a device that tests exhaled breath to indicate the amount of alcohol in the body or blood
Origin of Breathalyzerbreath (an)alyzer
[b-] such a device
A trademark for a device that detects and measures alcohol in expired air so as to determine the concentration of alcohol in a person's blood.
breathalyzer - Legal Definition
A device that measures that blood alcohol content of a person by analyzing the content of the moisture in her breath. Usually used by police when a person is suspected of driving while intoxicated.