Regretful means feeling sorry or disappointed about something you did or didn't do. When you're regretful, you wish you had made a different choice. You might feel regretful after snapping at your best friend during a bad day, or regretful about not practicing enough before a piano recital.

The feeling of being regretful is different from just feeling sad. Regret comes with the sense that you could have prevented the problem if you'd acted differently. A student might feel regretful about choosing to play video games instead of studying for a big test, because they knew better but made a poor choice anyway.

People who are regretful often want to make things right. Someone regretful about hurting a friend's feelings will usually apologize and try to repair the friendship.

The word can also describe something that expresses regret, like a regretful smile or a regretful tone of voice. When someone writes a regretful letter, they're expressing their sorrow about past events.