A nearly wiped out ethnic group of humans who breath very noisily through the mouth only. Major causes of death are from suffocation while: giving blow jobs, eating, or attempting to breathe from the nose.
1. Alex almost suffocated yesterday while eating; he must be a Mouth Breather.
2. Sadly, Alexis suffocated while giving Mr. Andryszak a blow job. She was the last female Mouth Breather.