A disservice is a harmful action that hurts someone, especially when you're supposed to be helping them. It's the opposite of a service: instead of doing something good, you do something that makes things worse.

When a coach tells players they did great even though they barely tried, that's a disservice because it keeps them from improving. When a teacher gives easy grades to avoid complaints, they're doing students a disservice by letting them graduate without really learning the material.

The word often appears in the phrase “do someone a disservice.” If you tell your friend their terrible haircut looks amazing just to be nice, you've done them a disservice because they needed honest feedback. If a newspaper publishes false information, it does readers a disservice by spreading confusion instead of truth.

A disservice usually happens when someone in a position to help chooses comfort or convenience over honesty or real assistance. The harm might not be obvious immediately, but it adds up. Some people say parents do their children a disservice when they solve every problem for them instead of teaching them to handle challenges themselves. Short-term help can create long-term weakness.