surnamedb.com is a good site. They say that: Recorded in several spellings as shown below, this is a very early English medieval surname. It derives from a personal name which may have been already present in the British Isles before the
Norman French conquest of 1066. This was Serilo possibly from the word searlu, meaning armour, and giving a possible meaning of defender or protector. The personal name was popular fro several centuries and is first recorded in the famous Domesday Book of 1086 in the county of Essex. Other examples include Serlo le Flemyng of Lincolnshire, in 1150, and Serle Gotokirke of Cambridgeshire in 1273. Early examples of the surname recordings include
Hugo Serle of Dorset in 1250, and
William Serell of Yorkshire, in the poll tax register of 1379.
Read more:
http://www.surnamedb.com/Surname/Searle#ixzz1eyjruZB1It is pronounced "like
Earl with an S" - good explanation! I've never seen it used as a fn in South
Africa, but these things happen. There is a well-known chain of shoe shops here called Searle's and their founder,
Aaron Searle, was a notable philanthropist.