divisive
Causing people to split into opposing sides or groups.
Divisive describes something or someone that splits people into opposing groups or creates conflict where harmony might have existed. When an issue is divisive, it drives people apart rather than bringing them together.
A divisive comment in your classroom might turn friends against each other. A divisive policy at school might make half the students angry while the other half cheers. The word suggests that whatever is divisive doesn't just create disagreement, it creates camps where people take sides and stop listening to each other.
Some topics are naturally divisive because people hold strong, different beliefs about them. But sometimes people or actions are unnecessarily divisive, meaning they create conflict when compromise or understanding would have been possible. A student who constantly pits classmates against each other is being divisive. A political leader whose speeches make citizens view their neighbors as enemies rather than as fellow community members is divisive.
The opposite of divisive is unifying, something that brings people together despite their differences. Notice that healthy disagreement isn't automatically divisive. People can debate ideas respectfully without being divisive. What makes something divisive is when it tears relationships apart and makes people see each other as opponents rather than as people who simply think differently.