In Welsh-language poetry, cynghanedd (Welsh pronunciation: [kəŋˈhaneð], literally "harmony") is the basic concept of sound-arrangement within one line, using stress, alliteration and rhyme.
Cynghanedd draws appears in this line from R. Williams Parry: Rhowch wedd wen / dan orchudd iâ ["place a white face under a veil of ice"]Here the consonant sequence {Rh Ch Dd [stress]} is repeated with different stressed vowels (short ⟨e⟩ and long ⟨â⟩).
A form of cynghanedd lusg known as "internal rhyme" (Breton : klotennoù diabarzh, enklotennoù or kenganez) was frequently used in Middle Breton, between the XIIth and XVIIth centuries, in poetry, like in Pemzec Leuenez Maria or in the sonnet from Français Moeam, and theatre like in lots of misterioù, religious pieces, such as Buhez Sante Barba'.
Two of the oldest works with internal rhymes are the Ivonet Omnes verses, which seem to be an old Breton lay and Dialog etre Arzuz Roe d'an bretounet ha Guiclaff, a prophetic text in dialogues.
This is an extract of An Dialog etre Arzur Roe d'an Bretounet ha Guynglaff (48-49 verses) : An tut a ilis diguyset An douar fallaff a roy guellaff [et]Though it isn't as used as cynghanedd in Modern Welsh, some authors have published some work using this internal rhyme in poetry (Alan Botrel)[1] or in the form of a lay like Lae Izold by Paskal Tabuteau.