A
Breton lai, also known as a
narrative lay or simply a
lay, is a form of medieval
French and English romance literature. Lais are short (typically 600–1000 lines),
rhymed tales of love and
chivalry, often involving supernatural and fairy-world Celtic motifs. The word "lay" or “lai” is thought to be derived from the Old High German and/or Old Middle German
leich, which means play, melody, or song, or as suggested by
Jack Zipes in
The Oxford Companion to Fairy Tales, the Irish word
laid (song).<ref "Z62>Zipes, 62