Scandalous means shocking or disgraceful in a way that damages someone's reputation or offends people's sense of what's right. When behavior is scandalous, it creates a scandal: public outrage and endless gossip about something that seems wrong or improper.

If a trusted teacher were caught cheating students out of their lunch money, that would be scandalous behavior. If a famous athlete were discovered lying about their achievements, the scandalous revelations would dominate the news. The word suggests behavior so shocking that it makes people talk and lose respect for whoever did it.

Sometimes people use scandalous more playfully, like calling a friend's messy room “absolutely scandalous” or saying it's scandalous that someone hasn't read a particular book yet. In these cases, they're exaggerating for effect, not describing something truly disgraceful.

The noun form is scandal. A scandal erupts when scandalous behavior becomes public knowledge. Throughout history, scandals have ended political careers, ruined reputations, and dominated conversations. What makes something scandalous is that it betrays trust or violates standards that people expect others to follow, making the wrongdoing feel especially shocking and public.