Egregious means shockingly bad or outrageous. When something is egregious, it's so obviously wrong or terrible that it stands out and demands attention.

An egregious error in a newspaper might claim that Abraham Lincoln was the first president (when everyone knows it was George Washington). An egregious foul in basketball might be when a player deliberately trips an opponent who's about to score. An egregious lie is one that's so ridiculous no reasonable person would believe it.

The word carries a sense of “How could anyone think this was okay?” When a restaurant makes an egregious mistake on your order, they brought you a completely different meal than what anyone at your table ordered. When a student makes an egregious spelling error, they might write “elefant” instead of “elephant” on their final draft after the teacher had corrected it three times already.

Egregious suggests that something is bad in a way that's impossible to miss or excuse. It's stronger than just “wrong” or “bad.” It means conspicuously, remarkably, and unacceptably awful.