Usually an old fart but not always. Basically a widemouth has is mouth agape and a stupid look on his face. Widemouths are usually stupid looking and live in their own reality. They always park in handicap spots even their only handicap is the lack of intelligence. A widemouth always drives his vehicle at slowest legal speed. A widemouth is cheap and will demand a senoir citizen's discount. I widemouth always thinks he is entitled to all benefits, discounts and government programs.
Look in the disabled parking spots, the widemouths are the ones that are not disabled or the ones that exit their vehicle with a cane which is tapped on the ground.