This is a rare and unusual surname is apparently medieval English. It is certainly recorded as Clash and sometimes Clashe, in the surviving church registers of the city of London, since at least Elizabethan times. Its meaning would seem to be a nickname for a cymbal player, or at least a player of percussion instruments. These in various forms have figured largely in military bands all over the world since before Roman times. However an alternative suggestion is that it was simply a nickname for somebody who was very noisy! Surnames from medieval nicknames are one of the largest groups amongst the surname listings, and there are some researchers who believe that originally most, if not quite all surnames, were essentially nicknames. Unfortunately without being present at the time that a surname was in some way adopted, if is often not possible to be precise with a meaning especially when five centuries or more have passed. According to the Oxford English Dictionary, the word "clash" is 16th century, which seems to be rather late, particulary given the known age of cymbals, and the "clashing" sound that they make. Early examples of recordings include Margery Clashe who married John Sanders at the church of St Dunstans in the East, Stepney, on January 16th 1563, and Thomas Clash who was christened at St Giles Fleet Street, on September 7th 1777.