A person who is given a high visibility jacket, at an event that is mostly staffed by volunteers, they get the High Vis Jacket and assume a false state of being better than everybody else, and basically become a bit of a wanker, bossing everyone around. This state, or disease, is called, Highvisitis

Abbreviation for “Dude Arguing Online”.

Plural: “DAOs”

Coined by Twitter user @karakittel.