what is the origin of the name sebastian
Sebastian (name) Sebastian is a given name. It comes from the Latin name Sebastianus meaning "from Sebastia", which was the ancient Greek name (Σεβάστεια) of the city now known as Sivas, located in the central portion of what is now Turkey.[1][2] The name of the city is derived from the Greek word σεβαστός (sebastos), "venerable",[3] which comes from σέβας (sebas), "awe, reverence, dread",[4] in turn from the verb σέβομαι (sebomai), "feel awe, scruple, be ashamed".[5] Sebastos was the Greek translation of the title Augustus, which was used for Roman emperors. Sebastian became a widely used name because it was the name of Saint Sebastian, a third-century Christian martyr.
Allen (surname) Allen is a Celtic surname, originating in Scotland, and common in Ireland, Wales and England. It is a variation of the surname MacAllen and may be derived from two separate sources: Ailin, in Scottish and Irish Gaelic, means both "little rock" and "harmony", or it may also be derived from the Celtic Aluinn, which means "handsome". Variant spellings include Alan, Allan, etc. The noble family of this surname, from which a branch went to Portugal, is descended of one Alanus de Buckenhall.