"" Variations in Spelling: Casborn, Casbourne, Casborne, Casbun, Caseborn, Caseborne, Casbourne, Casebourne, Cashborn, Cashburn, Casburn, Cassburn, Cassborn This unusual name is of English locational origin from Casebourne Wood in Hythe, Kent. The name derives form the Olde English "Caerse" meaning "cress" - an element usually found with endings indicating the growth of the plant in water. In this case, the second element is the Olde English "burna", a stream. The surname from this source is first recorded in the latter half of the 13th Century as Casebourne. A Coat of Arms was granted to the Casebourne family of Kent. Sable (black) two chevrons between three martlets or (gold). The Martlet indicates one who subsists on wings of Virture and Merit, having little land to rest on. The surname Casbourne was first found in Kent at Casebourne Wood in Hythe where they held a family seat as Lords of the Manor. The family name was first referenced in the 13th century when John de Caseburn held estates in that shire in 1275.
The Casbolt or Casebolt variant was first recorded in Cambridgeshire where Stephen Casebolt was recorded in the Subsidy Rolls of 1327.