From Wikipedia
Emeritus is an adjective that is used in the title of a retired professor, bishop or other professional. Emerita was used for women, but is rarely used today. The term is used when a person of importance in a given profession retires, so that his or her former rank can still be used in his or her title. This is particularly useful when establishing the authority a person might have to comment, lecture or write on a particular subject.
In the DJB, it is used as a title with any former position that a member held in front of it.
Examples:
- Consul Emeritus - Former Consul