Road hog is an idiom that dates back decades. We will examine the meaning of the common idiom road hog, where it came from, and some examples of its idiomatic usage in sentences.
A road hog is a driver of a vehicle who takes up more than his fair share of space on the road, straddles two lanes, drives fast and recklessly, or doesn’t consider the safety and rights of others on the road. A road hog is a dangerous driver and may cut off other drivers or prevent them from driving in their rightful space. The expression road hog equates an inconsiderate driver to the animal, the hog, which is considered to be greedy and selfish. The idiom road hog came into use in the mid-1880s, which is interesting, because the automobile was invented at that time (though there were very few of them on the road.)
Examples
Don’t be a road hog: if you sit in the middle lane it could cost you a £100 fine and three penalty points (Edinburgh Journal)
Are you a defensive driver, a weaver, a road hog, a speeder, or a tailgater? (Jamaica Gleaner)
If the SUV driver has been behaving and not cutting anyone else off or otherwise being a road hog, then I will let it in graciously. (Democrat and Chronicle)