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boi

guy

NounMasculine (gwrywaidd)C2/bɔi̯/

“boi” means “guy” in Welsh (masculine noun). Pronounced /bɔi̯/. Mutation forms: Treiglad Meddal → foi, Treiglad Trwynol → moi.

Mutation forms

In Welsh, the first letter of “boi” changes depending on the grammatical context. These are the mutated forms:

MutationForm
Base formboi
Treiglad Meddalfoi
Treiglad Trwynolmoi

Further reading

Welsh Mutations Explained — Soft, Nasal & Aspirate →Welsh Pronunciation — It's Actually Easier Than English →How to Learn Welsh as an Adult — A Step-by-Step Roadmap →Best Apps to Learn Welsh (2026) →Browse all Welsh vocabulary →

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