in English is:

insulation

Mutations

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

Use

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