A
breathalyzer or
breathalyser (a
portmanteau of
breath and
analyzer/analyser) is a device for estimating
blood alcohol content (BAC) from a breath sample.
Breathalyzer is the
brand name for the instrument that tests the alcohol level developed by inventor Robert Frank Borkenstein. It was registered as a trademark on May 13, 1954, but many people use the term to refer to any generic device for estimating
blood alcohol content .