A more thorough explanation:

concessum

Concessum is a Latin word that means "granted." In the past, judges used this term to show that they agreed with a point made during an argument. For example, a court might say that a particular idea was "granted by the whole court."

During a court case, a lawyer might argue that their client was not guilty of a crime because they were out of town at the time. If the judge agrees with this point, they might say "concessum" to show that they have granted this argument. This means that the lawyer can continue to build their case based on this point.

Another example might be during a debate in a classroom. If one student makes a good point, the teacher might say "concessum" to show that they agree with the point. This means that the student can continue to argue their case based on this point.