- A person or organization that has control or authority over someone else
- A court-appointed officer who aids a judge in the proceedings of a case by conducting hearings, making factual findings and legal conclusions, and performing related tasks
- The main or controlling authority over a group of similar things
- In certain cases, a court may assign a master to handle sensitive issues.
- In the slavery era, the unlawful condition was enforced by the master who had full control over the slave.
- The corporation served as the master entity, governing all related subsidiaries.