Interdict (in Catholic canon law) means that someone is not allowed to be part of some parts of the Church. This could mean not being allowed into Church buildings, not being able to take part in certain Church activities, or even not being allowed to take part in important religious events like baptisms or weddings. Sometimes, someone might be put under an interdict if they do something bad or if they disobey Church rules. This is a way for the Church to keep people in line and make sure they are following their laws and beliefs.