a poem or stanza of eight lines in which the first line is repeated as the fourth and seventh and the second line as the eighth with a rhyme scheme of ABaAabAB
Here's one of mine (actually the only one I'll own to)
So "My daughter and I in the woods gathered" appears in lines 1, 4 and 7.
The origin is supposed to be French medieval poetry but it's not uncommon now.
It looks so simple and yet it's a tricky one to master. It has been used cleverly for some horror poems as the simple, lyrical form and the repetitions can make scary stuff seem more menacing.
You can have a look at a triolet by Wendy Cope here, with some brilliant rhymes and another here.
It is a close cousin to other strict rhyming forms with repetition, such as the Rondeau, Villenelle and Pantoum. I may cover these in a later post in this very occasional series, but I'm not promising anything!