Origin: Irish Meaning: an Irish surname, the Anglicized form of Ó Sirideáin meaning "descendant of Sirideán", the latter having several possible meanings: "searcher", "wild man" or meaning "elf" with the diminutive suffix -an. I've also seen it as meaning "peaceful".  


Origin: English, Latin Meaning: first used by William Shakespeare for one of his characters. It could have been based on Latin Oliva, meaning olive, or a feminization of Oliver which comes from Old Norse: either from Alfihar meaning "elf army/warrior" or Olaf "ancestor's descendant"