cowbro means: Noun This is a small segment of the ever-pathetic bro outbreak. This bro calls Chino Hills, Norco and small portions of Corona home. Young boys and girls, who were raised on dairy farms as children, bring a milk-esc hooligan attitude to their bro images. These cowbros are not common in suburban areas, contrary to what is commonly believed. They have a badassy-ness that is more prominent than most bros. Cowbros often make their trucks dirty as a sign of achievement. They even attempt to use their absurd trucks. Their trucks are often modified with flared front fenders and an unevenly elevated front axle. They also have a truck bed that proudly displays a spare tire too large to fit through a door, rendering it useless. Although a tiny splinter of the bro sect cowbros look and act just like bros. We are sorry, there is no news. (in Community Dictionary, added by Adjuvant)