Lai is a type of both lyric poetry and songs that flourished first in 12th century France. It consists of one or many stanza, each with nine lines that have two rhymes. Later new forms of Lai emerged with two of them being more common – Virelai and Lai Noveau.
Virelai also comes from medieval France and it is used in both music and poetry. Being one of formes fixes along with the rondeau and the ballade it was the most popular from that was set to music in the thirteenth to the middle of the fifteenth centuries. It can have several stanzas with two rhymes, where the last rhyme is again the first rhyme in the next stanza.
Lai Nouveau on the other hand has an eight line stanza. First two lines are also used as two last lines in the next verse. The last verse has both lines but in the opposite order.