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costus

costly

AdjectiveC2

"costus" means "costly" in Welsh (adjective). Mutation forms: Treiglad Meddal → gostus, Treiglad Trwynol → nghostus, Treiglad Llaes → chostus.

Mutation forms

In Welsh, the first letter of "costus" changes depending on the grammatical context. These are the mutated forms:

MutationForm
Base formcostus
Treiglad Meddalgostus
Treiglad Trwynolnghostus
Treiglad Llaeschostus

"costus" in context

Nid oes ganddyn nhw unrhyw reolaeth dros y math o anifeiliaid na'u nifer, a all arwain at broblemau costus pan fydd tenantiaid yn gadael.

They have no control over the type or number of pets, which can lead to costly issues when tenants leave.

B2

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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