Rannaicheacht, randaigecht chethar-chubaid garit rocamarcach is:
• a Rannaicheacht (versification) gharid (clipped) with two-syllable end words. (chethar-chubaid)
• written in any number of quatrains.
• syllabic 3-7-7-7..
• alliterated, 2 word alliteration in each line.
• written with aicill rhyme, the end word of L3 internally rhymes with L4.
• written with the defining features of all ancient Celtic forms, cywdydd and dunadh.
x (x a)
x x x x x (x a)
x x x x x (x B)
x x bx x (x a)
Pasted from http://www.poetrymagnumopus.com/index.php?showtopic=1170#chethar
My thanks to Judi Van Gorder for years of work on this fine PMO resource.
Cywdydd = 7 syllable lines, couplets ending alternatively stressed and unstressed
Dunadh = Ending as it start