a list of people. countries. etc. who are considered by a particular authority or group to be unacceptable and who should be avoided and not trusted

to put someone`s name on a blacklist.

to put someone’s name on a list of people who are considered not acceptable. which keeps the person from getting jobs. going certain places. or doing particular things.

a list of companies. organizations. or people that have a bad reputation or have done something illegal and that other organizations do not do business with because of this.

to decide that you will not do business with an organization or person.