Cynghanedd

In Welsh-language poetry, cynghanedd (Welsh pronunciation: [kəŋ̊ˈhaneð], literally "harmony") is the basic concept of sound-arrangement within one line, using stress, alliteration and rhyme. The various forms of cynghanedd show up in the definitions of all formal Welsh verse forms, such as the awdl and cerdd dafod. Though of ancient origin, cynghanedd and variations of it are still used today by many Welsh-language poets. A number of poets have experimented with using cynghanedd in English-language verse, for instance Gerard Manley Hopkins. Some of Dylan Thomas's work is also influenced by cynghanedd.

The first example below is from the poem Cywydd y Cedor, by the fifteenth-century poet Gwerful Mechain. The caesuras are marked with slashes ("/") and rhyming parts are marked in bold. Note that Dd, Ll and Ch are single consonants (digraphs) in the Welsh alphabet.

All consonants surrounding the main stressed vowel before the caesura must be repeated after it in the same order. However, the final consonants of the final words of each half of the line must be different, as must the main stressed vowel of each half. For example:

Here we see the pattern {c l dd dd [accent] l} present on both sides of the caesura. The stressed vowels are <a> (a short monophthong) and <wy> (the diphthong /uj/).

In cynghanedd groes there are no consonants in the second half of the line which are not part of the consonantal echoing. The vowels other than those under the stress may be of any kind.

Exactly as in cynghanedd groes, except that there are consonants at the beginning of the second half of the line which are not present in the series of 'echoed' consonants:

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