Incredulous means unwilling or unable to believe something because it seems too unlikely or surprising to be true. When you're incredulous, you're skeptical or doubtful, often because what you're hearing sounds impossible or absurd.

If your friend told you they just saw a unicorn in their backyard, you'd probably give them an incredulous look: raised eyebrows, a doubtful expression that says “Really? Are you serious?” When a teacher hears an incredibly far-fetched excuse for missing homework, like “My dog ate it, then my cat buried it, then aliens took it,” she might respond with an incredulous laugh.

The word captures that specific feeling when something strikes you as so unbelievable that you can't accept it at face value. A student might listen with incredulous disbelief as someone claims they finished a 500-page book in ten minutes. Scientists often approach wild claims with incredulous skepticism, demanding evidence before they'll believe extraordinary statements.

Don't confuse incredulous with incredible, which means unbelievable or amazing. When you're incredulous, you're the one who doesn't believe. When something is incredible, it's the thing that's hard to believe. You might be incredulous about an incredible story.