Lord Mayor was the title of the head official of a British city or town.
A male Lord Mayor of Cardiff was killed in the Auton invasion of London on 5 March 2005. (AUDIO: One Rule) He was eventually succeeded by Blon Fel-Fotch Passameer-Day Slitheen, posing as Margaret Blaine. The position was once again left vacant in September 2006 when Blon's plot to escape and destroy the Earth was foiled by the Ninth Doctor, who used the Heart of the TARDIS to regress her into an egg before returning her to Raxacoricofallapatorius. (TV: Boom Town)