The first name Eileen is of Latin, Greek, French, Irish, Celtic/Gaelic, Scottish origin. It is often a girl name. It has the following meaning(s):
Latin: Variant of Evelina: Latinized Form of the Old German Name Avelina. Famous Bearer: Fanny Burney's Novel 'Evelina'
Greek: Variant of Helen: Shining Light. The Bright One. Helen of Troy, Whose Elopement With Paris Sparked the Trojan War, Was the Daughter of Zeus and Wife of Menelaus, King of Sparta
French: Variant of Evelyn: from a Surname Derived from the Old French 'Aveline' Meaning Hazelnut
Irish: She Who is Life Giving (Elaine, Ilene)
Irish: Light. from the Name Eibhlin, Derived from Evelyn or Evelina
Celtic/Gaelic: Light, from Helen
Scottish: Hazelnut; an Anglicized Form of Eibhlin. Variations: Aileen, Alina, Aline. Pet: Ailie, Eilie. (I-leen)