in English is:

proficiency

Mutations

Soft:(no mutation)
Nasal:(no mutation)
Aspirate:(no mutation)

Use

yr hyfedredd hwn
fy hyfedredd i
dy hyfedredd di
ei hyfedredd ef/o
ei hyfedredd hi
ein hyfedredd ni
eich hyfedredd chi
eu hyfedredd nhw/hwy
External

Dictionary Portal

This is a library of dictionaries and other online resources where you can search further for hyfedredd*:

Specialist Dictionaries
Glossaries
Terminology
Encyclopedia
Example Sentences
Sentences containing:

*External websites will be opened in a new window.