This name originally was used a surname, which is derived from “Aveline”, a feminine Norman-French diminutive of the name “Ava” from “avila” (derived from the Germanic element “av / avi”, of unknown meaning, possibly "desired"). Evelyn is also sometimes used as an Anglicization of the Irish Gaelic Aibhilín and Éibhleann. Aibhilín is a variant form of Eibhlín, which is also derived from the Norman-French Aveline. Éibhleann, on the other hand, is said to be derived from the Old Irish “óiph”, meaning “radiance, beauty”; a variant of Éibhliu, used in English as Evilin. Other scholars support the theory that the name "Evelyn" means "hazelnut". Teresa of Ávila (1515–1582), was a prominent Spanish mystic, Roman Catholic saint, Carmelite nun, an author of the Counter-Reformation and theologian of contemplative life through mental prayer.