Breton mutations

Like all modern Celtic languages, Breton is characterised by initial consonant mutations, which are changes to the initial sound of a word caused by certain syntactic or morphological environments. In addition Breton, like French, has a number of purely phonological sandhi features caused when certain sounds come into contact with others.

The mutations are divided into four main groups, according to the changes they cause: soft mutation (Breton kemmadurioù dre vlotaat), hard mutation (kemmadurioù dre galetaat), spirant mutation (kemmadurioù c'hwezhadenniñ) and mixed mutation (kemmadurioù mesket). There are also a number of defective (or incomplete) mutations which affect only certain words or certain letters.

The main mutations cause the following changes:

The role which initial mutations play in Breton grammar can be divided into three categories (which are not mutually exclusive):

The soft mutation is by far the most frequent mutation in Breton, both in terms of the number of consonants it affects and the number of environments in which it occurs.

The definite article al/an/ar and the indefinite ul/un/ur cause the soft mutation of:

Nouns beginning with d- and a few others do not mutate after the articles.

The following grammatical words cause mutations to a following word:

The soft mutation occurs in:

These mutations are limited. When the first word ends in a vowel or -l, -r, -m, -n it causes the soft mutation wherever possible, but when the first word ends in any other consonant only the consonants g-, gw-, m-, b- change in the following words.

Spirant mutation transforms three unvoiced plosive consonants into fricatives: p /p/ → f /v̥/, t /t/ → z /h/ and k /k/ → c'h /x/.

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