Reproachful means expressing disappointment or disapproval, usually through your tone of voice, facial expression, or the way you speak to someone. When your mom gives you a reproachful look after you track mud through the house, you can tell she's disappointed without her saying a word. When a teacher uses a reproachful tone while saying “I expected better from you,” the disappointment comes through clearly.

The word suggests a kind of gentle criticism that can make someone feel guilty or ashamed because they know they've let someone down. It's not angry shouting or harsh punishment: it's that quiet disappointment that somehow feels worse. If your best friend speaks to you reproachfully after you forgot their birthday, their hurt feelings show in how they talk to you.

A reproach (the noun form) is the actual expression of disappointment. You might avoid your grandfather's reproach by finishing your homework before playing video games. The feeling behind reproachful words or looks is that someone trusted you or expected something from you, and you didn't follow through. That disappointment, delivered reproachfully, can sometimes motivate people to do better next time more effectively than anger does.