Lord Mayor of the City of London

The Right Honourable the Lord Mayor of London is the legal title for the Mayor of (and head of) the City of London Corporation. The Lord Mayor of London is to be distinguished from the Mayor of London; the former is an officer only of the City of London, while the Mayor of London is the Mayor of Greater London and as such governs a much larger area. Within the City of London, the Lord Mayor has precedence over other individuals and has various special powers, rights and privileges.

The Wikipedia page is