Its source is Helen, an English name meaning "Sun ray."
Though this name is conventionally considered to be a French-inspired variation of the Greek-derived Helen, there is evidence that it could have originated from an entirely different source.
The Arthurian legends feature a character named Elaine, who falls in love with the righteous knight Sir Lancelot. First appearing in Thomas Malory's 15th century re-telling of those tales, Le Morte d'Arthur, the character was picked up by Tennyson for his 1859 Idylls of the King. Tennyson's work was probably instrumental in introducing Elaine to the list of English girls' names.
Many names from the Arthurian legends are of ancient Celtic origin. This has led scholars to suggest a derivation for Elaine from a Welsh expression meaning ''young deer.''