At What Point Does Vomiting Become 'Projectile Vomiting'?

The term "projectile vomiting" is defined as vomiting forcefully. My question is how is that any different than normal everyday vomiting? All vomiting is "projectile" otherwise it wouldn't come out to begin with. Is projectile vomiting just a matter of your head being tilted up so the barf flies outward? Does it have to do with the miles per hour the vomit is expelled?

Even when you're really sick you have at least a half second to tilt your head down. I think the only reason projectile vomiting exists is because people don't want to ruin their shoes. How selfish is that? You'd rather puke your disgusting norovirus strain on another person's face than mess up your fancy high heels. If you're going to go through all the trouble to get drunk and go to the county fair dressed like a woman the least you can do is show a little etiquette, Uncle Geoff!