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, hard mutation, spirant mutation and mixed mutation. There are also a number of defective mutations which affect only certain words or certain letters.
Summary of sound changes
The main mutations cause the following changes:| Unmutated | Soft | Spirant | Hard | Mixed |
| P | B | F | ||
| T | D | Z | ||
| K | G | C'h | ||
| B | V | P | V | |
| D | Z | T | T | |
| G | C'h | K | C'h | |
| Gw | W | Kw | W | |
| M | V | Mh /ʰm/ | V |
Functions of mutations
The role which initial mutations play in Breton grammar can be divided into three categories :- Linking mutations – these occur systematically after certain words called mutators, of which there are around 100 in Breton.
- Gender-number-distinctive mutations – these occur after the articles and in postposed adjectives to mark gender and number.
- Mutations of recognition – these mark the distinction between homophones and are useful in the comprehension of the spoken language.
Soft mutation
Environments
After definite and indefinite articles
The definite article al/an/ar and the indefinite ul/un/ur cause the soft mutation of:- Most feminine singular nouns:
- Masculine plural nouns denoting people:
After proclitics
The following grammatical words cause mutations to a following word:- The prepositions da, dre, a, war, dindan, eme, en ur:
- The interrogative pronoun pe "what":
- The possessive pronouns da "your", e "his":
- The verbal particles a, ne, na, ez, ra, en em:
- The numerals daou "two ", div "two ":
- The conjunctions pa "if, when", pe "or", tra "while"
- The adverb re "too":
- The pronouns holl "all", re "those, ones", hini "that, one":
After adjectives and nouns
- Adjectives following feminine singular nouns:
- Adjectives following masculine plural nouns referring to people:
- Nouns following adjectives:
Spirant mutation
Environments
The mutation occurs following:- The possessive pronouns he "her", o "their, ma/va "my" and hon "our":
- The numerals tri "three ", teir "three ", pevar "four ", peder "four ", nav "nine":
Defective mutations
- The mutation of t and k occurs following the infixed pronoun 'm "me", da'm "to my" and em "in my":
- Mutation of k occurs following hor "our":
- The word Pask "Easter" becomes Fask following the days Sul "Sunday" and Lun "Monday".
Hard mutation
Environments
The mutation is caused by:- Possessive pronoun ho "your ":
- Infixed pronoun 'z "your ", da'z "to your ", ez "in your ":
Mixed mutation
Environments
The mixed mutation occurs after:- The verbal particles e and o
- The conjunction ma "if"
Mutations and external sandhi
Nasalisation
The true nasal mutation which occurs in Welsh never occurred in Breton and Cornish, where it was replaced by the Spirant Mutation. But there was assimilation of the voiced plosives, particularly b, d to a preceding nasal and this was often written in Middle Breton.Today it is only written with an nor "the door" but can still be heard dialectally in other words, e.g. an den "one" and bennak "some".
Spirantisation
Today, a number of nouns beginning with k change to c'h following the articles ar "the" and ur "a":Although this is the same process seen in the spirant mutation, it is really an external sandhi which has become fixed in writing.
"Interchangeable" consonants
Breton has a series of 'interchangeable' consonants, composed of plosives and fricatives. When these sounds occur word-finally, they may be pronounced voiceless or voiced depending on the word that follows:- The sounds are voiceless when the word is followed by a voiceless sound or a pause.
- The sounds are voiced when the following word begins with a voiced consonant or a vowel.
| Voiceless | Voiced | Orthography |
These changes are never written but occur regularly, regardless of how the final consonant is spelled:
Exceptions
- When two equivalent or identical consonants come together, both consonants become voiceless:
- Some words ending in s/z or ch/j resist voicing.
Orthography of mutations
In Old and Middle Breton, it was extremely rare to write the consonant mutations. Around the 17th century, the Jesuits started to learn Breton and introduced the writing of mutations.Sometimes, the mutated letter is written before the radical letter in the style of the Gaelic languages, to make recognition easier. This is largely confined to proper nouns.
Some processes which are properly part of external sandhi have become crystallised in the written language, whilst others have not.