Initial Consonant Mutations
In Welsh, the first letter of a word can change because of the word in front of it. These changes are called mutations.
How It Works
Mutations are part of Welsh grammar, and they can carry meaning. In ei gath e (his cat) and ei chath hi (her cat), the word ei is the same, but the change to cath tells you whose cat it is.
The three main kinds:
- Soft mutation, the most common: p→b, t→d, c→g, b→f, d→dd, g disappears, m→f, ll→l, rh→r. i Gaerdydd (to Cardiff). See soft mutation.
- Nasal mutation: p→mh, t→nh, c→ngh, b→m, d→n, g→ng. yng Nghaerdydd (in Cardiff). See nasal mutation.
- Aspirate mutation: p→ph, t→th, c→ch. a Chaerdydd (and Cardiff). See aspirate mutation.
Words that start with a vowel can gain an h after a few words; see h-prothesis. Later you will also meet mixed mutation. Among the consonants, only the nine letters p, t, c, b, d, g, m, ll and rh ever change; every other consonant stays the same.
What causes a mutation? Usually a particular word just before, such as i (to), o (from), fy (my) or a (and). Sometimes it is the word's position in the sentence.
Dictionary tip. If you cannot find a word, try undoing a mutation:
- g, b, d at the start may have been c, p, t (gath → cath)
- f may have been b or m (fara → bara, fam → mam); dd may have been d; l may have been ll; r may have been rh
- a vowel at the start may have lost a g (ardd → gardd)
- ngh, mh, nh may have been c, p, t; ng, m, n may have been g, b, d
- ch, ph, th may have been c, p, t
Take it step by step. People will understand you if you miss one, and in relaxed everyday speech even fluent speakers do not make every mutation every time.
Examples (6)
- Dw i'n mynd i Gaerdydd.
I'm going to Cardiff.
Soft mutation: Caerdydd becomes Gaerdydd after i (to).
- Mae fy chwaer i'n gweithio yng Nghaerdydd.
My sister works in Cardiff.
Nasal mutation: Caerdydd becomes Nghaerdydd after yn (in), which becomes yng.
- Dw i wedi byw yn Abertawe a Chaerdydd.
I've lived in Swansea and Cardiff.
Aspirate mutation: Caerdydd becomes Chaerdydd after a (and).
- Mae ei gath e'n ddu.
His cat is black.
Ei meaning his causes soft mutation: cath becomes gath. South: e. In the North: Mae ei gath o'n ddu.
- Mae ei chath hi'n wyn.
Her cat is white.
Ei meaning her causes aspirate mutation: cath becomes chath.
- Dyma fy nghath i, Mali.
This is my cat, Mali.
Fy (my) causes nasal mutation: cath becomes nghath.
How It Connects
Related Patterns
- Soft Mutation
The most common kind of mutation.
Level 1 - Nasal Mutation
The mutation after fy (my) and yn (in).
Level 2 - Aspirate Mutation
The mutation after a (and) and ei (her).
Level 2 - Adding H Before Vowels
How words starting with a vowel can gain an h.
Level 2 - Mixed Mutation
A later mix of soft and aspirate changes.
Level 3 - Words That Resist Mutation
Some words stay the same where you might expect a change.
Level 5
Practice Initial Consonant Mutations in Bubblegum
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